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BACKGROUND OF THE INVENTION
In the diagnosis and/or treatment of disorders of the body, it is known to
physically alter the condition or function of hollow viscera or other
internal body vessels. Surgical procedures on such vessels include
reconstruction of natural tissue, substitution and bypass techniques with
natural or artificial implants. Surgery is recognized as always carrying
some degree of risk to the patient, both during its actual performance and
in postoperative complications or side effects. These risks, of course,
are of major concern when the surgery involves the invasion of the great
cavity of the trunk of the human body. This is especially ture in
treatment of such viscera as the heart, liver, or intestines, and in
particular when such surgery involves these organs themselves.
In surgical treatment of obesity, for example, the abdominal cavity is
exposed to allow reconstruction of the digestive tract, in essence, to
reduce the internal surface area available for food digestion or
absorption of digested substances. The former technique, a gastric bypass,
may be accomplished by anastomosing a minor portion of the stomach to the
jejunum while leaving the major portion connected to the duodenum. The
latter of these techniques, an intestinal bypass, involves the
short-circuiting of a majority of the combined lengths of the jejunum and
ileum by connecting the first part of the jejunum to the last part of the
ileum.
Both of these operations are deemed to involve such high risk to the
patient that they are considered only as a lifesaving undertaking for
morbidly obese individuals. Beyond statistically significant operative and
overall mortality rates, reported complications following the gastric
bypass include marginal ulcers and wound infections. The intestinal bypass
involves similar mortality rates and, reportedly, a greater number of
postoperative complications and side effects. These include pulmonary
emboli, wound infections, gastrointestinal hemorrhage, renal failure, and
numerous other disorders. The nature, severity, and frequency of these
problems have in fact led to doubts as to the advisability of the
techniques for treatment of obesity.
SUMMARY OF THE INVENTION
The invention provides a method and means for isolating the internal walls
of hollow viscera or other body vessels from contact with materials, both
fluids and solids, occurring naturally, ingested, or otherwise introduced
into a body vessel. Isolation of a body vessel, according to the
invention, is achieved by positioning and anchoring a sleeve, impervious
to materials sought to be isolated within the vessel, in such a manner
that the sleeve, at least adjacent its upstream end, is in sealing
engagement with the surrounding interior tissue of the vessel. Material
otherwise normally flowing into the vessel and being capable of
interracting with the vessel to the detriment of the patient's health is
thereby contained and rendered ineffectual or on unaffected by the vessel.
An important application of the invention is the nonsurgical treatment of
obesity through reduction in the effective natural surface area of the
digestive tract. In one disclosed embodiment, a sleeve impervious to both
gastric secretions and food substances is disposed within the stomach in a
manner which prevents contact between these gastric secretions and food
substances. More specifically, the sleeve acts as a liner for at least a
portion of the internal stomach area while also providing a conduit for
food passing through the stomach. The sleeve, which is capable of
establishing a circumferential, substantially fluidtight seal with the
walls of the stomach adjacent its upstream end, may be any desired length
so that a suitable portion of the internal stomach area is rendered
ineffectual in the digestive process. Consequently, the sleeve is
operative to limit the efficiency of food absorption in the small
intestine.
As disclosed, the sleeve may be introduced into the stomach through the
oral cavity and esophagus. In the preferred embodiment, the sleeve is
sufficiently flexible to be collapsed into a unit of relatively low bulk
for ease of passage through the posterior pharynx and esophagus. Upon
reaching a desired position in the stomach, the sleeve is expanded by
means carried with the sleeve, including a flexible tube trailing the
sleeve. A source of pressurized fluid external of the patient's body is
operably connected to the expanding means through this trailing tube to
expand the sleeve into sealing engagement with the walls of the stomach.
The sleeve may be additionally restrained against further movement along
the digestive tract by anchoring the trailing tube or a separate parallel
element upstream in the digestive tract.
The tissue isolating function of the disclosed sleeve, in addition to
control of the mechanism of digestion, has numerous other applications in
diagnosis or treatment of body disorders. For example, the sleeve may be
used to chemically and/or physically protect tissue which has been
ulcerated, herniated, fissured, or the like from natural body fluids.
Ruptured blood vessels or aneurysms may be protected from further damage
and allowed to heal by isolating the effect of normal blood pressure from
the vessel by containing it within the sleeve.
Stenosis or a sclerotic closing of an artery may be expanded from within by
the use of internal compression while still allowing blood to pass
through, especially in those individuals whose disease is so far advanced
that a graft could not be sutured to the distal portion of the vessel.
Still further, where desired, one or more tubes connected to the sleeve
may be arranged to provide communication between the annular zone
intermediate the protected vessel and the outer surface of the sleeve for
introduction of medicines or aspiration of fluids from the zone.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a vessel-insertable medical sleeve unit
constructed in accordance with the invention;
FIG. 2 is a fragmentary, cross sectional view on an enlarged scale through
the wall of the sleeve unit, taken along the line 2--2 of FIG. 1;
FIG. 2a is a fragmentary, cross sectional view similar to FIG. 3, taken
along the line 2.sub.a --2.sub.a of FIG. 1;
FIG. 3 is a fragmentary, cross sectional view on an enlarged scale, taken
along the line 3--3 of FIG. 1 of a trailing filament of the sleeve unit;
FIG. 4 is a schematic illustration of a manner of use of the sleeve to
control obesity;
FIG. 5 is a view of the sleeve unit in a compacted condition and contained
within a dilator shell for installation;
FIG. 6 is a view of the sleeve unit depicting an intermediate configuration
in a progressive sequence of expansion from the condition of FIG. 4;
FIG. 7 is a view of the sleeve progressed in its transition from FIG. 5
through FIG. 6 to a fully expanded configuration essentially corresponding
to FIG. 4;
FIG. 8 is a schematic view of a second embodiment of the sleeve of the
invention employed within an aorta; and
FIG. 9 is a sectional view in a longitudinal plane of a ring balloon and
associated implantable sleeve disposed in a blood vessel of an animal body
.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings, and in particular to FIG. 1, there is shown
a sleeve unit 10 in the form of a cylindrical, tubular sheath 11 and one
or more inflator ring balloons 12-14. The sheath 11 in the illustrated
example if a flexible membrane of nontoxic material impervious and
chemically resistant to body fluids which it is expected to encounter. The
sheath material is selected from a variety of known plastic and/or
elastomeric substances. The sheath 11 may be extruded, rolled, or
otherwise formed, as desired, into a tube with or without a longitudinal
seam or seams.
The inflator ring balloons 12-14 as indicated in FIG. 1 are flexible,
hollow, torroid-like elements spaced axially along the interior of the
sheath 11. As indicated, the rings 12 and 14 are adjacent opposite ends 16
and 17 of the sheath 11. The ring balloons 12-14 may be formed of a
material the same as or like that of the sheath 11, and are either
integrally formed thereon or are bonded thereto by heat, adhesive, solvent
or like means. While the sheath 11 is illustrated as a cylinder, it will
be understood that it may take other configurations, such as a frustum or
a sphere truncated adjacent opposite poles, or a tubular elbow of constant
or varying diameter. The sleeve unit 10 includes at least one, and
preferably two, trailing hollow filaments 20,21 connected thereto by
bonding or other suitable means. These filaments 20,21 may be made of the
same or similar material as the sheath 11. In the illustrated case, each
of the filaments 20-21 includes a central lumen 22 and an auxiliary lumen
23. When desired or necessary, additional lumens may be disposed in the
wall of each filament 20-21. Ideally, one of the filaments 20 has its
central lumen 22 in fluid communication with an upstream one 12 of the
ring balloons, while the other filament 21 has its central lumen 22 in
fluid communication with the remaining ring balloons 13 and 14.
As suggested in FIG. 3, longitudinally spaced, generally radial passages 26
provide communication from the auxiliary lumens 23 of each filament 20, 21
through the adjacent wall of the sheath 11 to points external of the
sleeve unit 10. The exterior surface of the filaments 20,21 and internal
surface of the sheath 11 are sealed to one another by suitable means, such
as bonding or the like, at their points of tangency so that fluids in the
auxiliary lumens cannot escape into the interior, designated 27, of the
sheath 11 at the radial passages or apertures 26.
The sleeve unit 10 is implanted in a body vessel in order to isolate the
walls of such vessel from fluids normally flowing into it. FIG. 4
illustrates a manner of use of the sleeve unit 10 to isolate the internal
surface area or lumen, designated 31, of a human stomach 32 and its
secretions from food substances passing through it. The sleeve unit 10 is
implanted in the stomach 32 in a nonsurgical manner by passing it through
an oral cavity 33, pharynx 34, and esophagus 35. To facilitate
introduction of the sleeve unit 10 into the stomach 32, the sleeve unit is
folded on itself accordion fashion to reduce its length and diameter. In
its folded or compacted state, the sleeve unit 10 is contained within a
dilator shell or cup 37 (FIGS. 5 and 6). The dilator shell 37 has a
rounded profile for ease of passage through the natural lumen of the
digestive tract, generally indicated at 39 (FIG. 4). The dilator shell 37
carrying the collapsed sleeve unit 10 is inserted through the epiglotis,
whereupon natural swallowing action allows it to be readily advanced into
the stomach 32.
Upon reaching the stomach 32, one or both of the central lumens 22 of the
filaments 20,21 are connected to a source of pressurized fluid, such as
air, ordinarily external of the oral cavity 33. Lower sections of the
filaments 20, 21 longitudinally associated with the sheath 11 develop
forces upon pressurization, tending to unfold themselves along with the
sheath. FIG. 6 depicts this action, wherein the dilator shell 37 is
released from the sleeve unit 10 and allowed to pass through the lower
portion of the digestive tract 39. The sleeve unit 10 in a continuous
sequence of movement expands from the intermediate position of FIG. 6 to
that of FIG. 7.
The final position of the sleeve unit 10 in the stomach 32 may be adjusted
by pumping fluid through the auxiliary lumens 23 in such a manner that it
issues from the passages 26 as a jet developing a reaction force to shift
the adjacent area of the sleeve unit in one direction or another,
depending on the orientation of the passages. These passages 26 may be
provided with either an axial or tangential component in their orientation
with respect to the axial direction of the sleeve to cause corresponding
axial or turning movement of the sleeve. Preferably, the sleeve unit 10,
including the filaments 20, 21 and ring balloons 12-14, is provided with
sufficient radiopaque material to permit external observation of its
position and configuration. When the position of the sleeve unit 10 is
satisfactory, the ring balloons 12-14 are finally inflated through the
central filament lumens 22, again by a source of pressurized fluid
external of the patient's body. Inflation of the ring balloons 12-14
causes them, in the manner of circumferential stiffening ribs, to fully
expand the sleeve into tight sealing engagement with the interior surface
31 of the stomach vessel 32. The ends of the filaments 20,21 distal from
the sleeve unit 10 are anchored to a posterior tooth or prosthesis by
suitable fastening means or are sutured in place. The central or main
lumens 22 of the filaments 20,21 are closed at these anchoring points by
heat sealing, plugging, or the like, to indefinitely maintain a
pressurized state in the connected ring balloons 12-14 to keep the
adjacent sleeve areas in fluidtight engagement with the stomach wall 31.
Where desired, for example, to release fluids secreted by the stomach
walls 31, the middle and lower ring balloons 13, 14 may be intermittently
or permanently depressurized so that these fluids may pass through the
remainder of the digestive tract. Alternatively, fluids secreted by the
stomach area 31 shielded by the sleeve unit 10 may be aspirated through
the oral cavity by way of the auxiliary lumens 23 and passages 26.
Moreover, if desired, medicine may be carried into the annular zone
defined between the sheath 11 and stomach walls 31 through the oral cavity
by way of the auxiliary lumens 23 and passages 26.
The sleeve unit 10, by isolating the walls 31 of the stomach 32 from
ingested food passing through it, reduces the digestive efficiency of the
stomach. This results from interference with the normal contact of gastric
juices, secreted by the stomach walls 31, on such food and the inability
of the intestines of the lower digestive tract to absorb undigested food.
Thus, the patient, while consuming food in even large quantities, is
enabled to lose weight, since only a limited amount of the ingested food
is ultimately absorbed.
Various other uses of the disclosed sleeve 10 or its equivalents are
contemplated in the treatment of body disorders. For instance, the sleeve
10 may be disposed in the small intestine, rather than in the stomach, to
directly reduce the effective area of the intestine available for
absorption, again for the control of obesity. When disposed in the
stomach, the sleeve may be utilized to medicate an ulcerous zone and
isolate it from gastric juices to hasten normal recovery.
Referring now to FIG. 8, there is shown a second embodiment of the
invention wherein a sleeve 25 is disposed within a human aorta 30 and
associated right and left common iliac arteries 31, 32. The sleeve 25 is
bifurcated at one end to provide a pair of branches 25a and 25b
corresponding to the right and left common iliac arteries 31, 32
respectively. The sleeve 25 has a construction essentially the same as the
earlier-described sleeve 10. Ring balloons 33 are spaced axially along the
sleeve including the branch portions 25a,25b. Each of the ring balloons 33
is in fluid communication with at least one hollow filament 34,35 for
purposes of inflation.
The sleeve 25 is advantageously employed in cases of advanced blood vessel
disease where a patient's tissue is such that it is impossible to sew or
anastomose it with grafts or artificial vessels. An incision 41 is made in
the vessel 30 to allow the positioning of the sleeve 25 therein. The
sleeve 25 is expanded into position by directing fluid pressure into the
elongated filaments 34,35 in any suitable manner such as disclosed above
with use of free extensions (not shown) of these filaments.
The sleeve 25 is anchored in the vessel 30, for example, by sutures 42 near
the incision 41, while the distal portion of the sleeve remains free. One
or more holes 43 may be cut into the wall of the sleeve prior to placement
within the vessel to provide blood flow to various arterial branches 46.
The sleeve 25 is preferably formed of relatively inelastic material or
otherwise is circumferentially reinforced with inelastic material along
its length so that the pressure of blood flowing through the sleeve is
effectively isolated from the vessel 30.
FIG. 9 illustrates another aspect of the invention wherein an inflatable
ring balloon 50 is used to implant a prosthetic sleeve 51 at an area of a
body vessel requiring expansion, reinforcement, isolation, or like
treatment. The illustrated vessel 52 is a blood vessel previously blocked
by plaque formation 53 and requiring expansion. A catheter 54 having a
dilator annular balloon 50 at its free end and the sleeve 51 surrounding
the balloon is threaded through the vessel 52 from an incision made in the
vessel at a point remote from the area of plaque by known surgical
procedures until the balloon and sleeve are within the area of blockage.
When the balloon 50 and sleeve 51 are thus located within the plaque 53,
the balloon is inflated to expand the plaque and the vessel 52. The
balloon 50 has inner and outer imperforate walls 56, 57 which are
circumferentially joined in a fluidtight manner at their ends. The annular
space 58 between the sleeve walls 56 and 57 communicates with the lumen of
the catheter tube 54. The balloon 50 is formed of any suitable plastic or
rubber material which may be folded and/or expanded.
In a similar manner, the sleeve 51 has imperforate, flexible inner and
outer walls 61,62 which are circumferentially joined in a fluidtight
manner at their ends. An interior space 63 between the walls 61, 62 of the
sleeve communicates with the interior of a tube 64 which extends along the
catheter tube 54 to a point outside the vessel 52. The outer sleeve wall
62 may be formed of Dacron and can include a weave or mesh outer layer
(not shown) which will lie against and adhere to the wall of the blood
vessel. The inner wall 61 may be formed of Teflon so that cells will not
readily adhere to this area.
The sleeve space 63 contains a fluid plastic material 66 which is caused to
become solidified, preferably to a semirigid state after the balloon 50
has been expanded against the plaque 53. A suitable material for filling
the sleeve space 63 Silastic 382, medical grade elastomer, marketed by Dow
Corning Corporation, of Midland, Mich., U.S.A. This material originates as
two separate liquids: an opaque viscous elastomer base and a catalyst. The
elastomer base is composed of polydimethylsiloxane and silica. The
stiffness of this silastic material is controllable by varying the
percentage of silica used. The concentration of catalyst can be varied, as
prescribed by the supplier, to control the working time from four to one
hundred minutes, as desired. Preferably, the components of the material 66
are thoroughly mixed and subsequently introduced into the sleeve space 63
just prior to the catheterization operation in which the balloon 50,
sleeve 51, and catheter 54 are inserted into the vessel.
When being manipulated along the vessel, the balloon 50 and sleeve 51
encircling it are in an uninflated, collapsed state. The collapsed state
can be maintained by wrapping the sleeve 51 on itself and superficially
heat-bonding it at appropriate folds. The balloon 50, once in position
within the area of the vessel to be treated, is inflated with a gas or
fluid supplied under pressure through the catheter 54. The pressure of
this inflating fluid is sufficient to break the light heat bonds holding
the folds of the sleeve 51 together and to expand the sleeve and plaque 53
in the vessel 52 to the required degree. The inflation pressure is
maintained for a period sufficient for setting of the liquid 66 in the
sleeve space 63 to become solidified into its semirigid state. A central
passage 68 in the balloon 50 allows blood to continue to flow through the
vessel 52 while the balloon is in place.
After the sleeve material 66 has solidifed into a semirigid structure, the
balloon 50 is deflated through the catheter 54 and is withdrawn from the
sleeve by pulling the catheter. The sleeve 51 remains in place, with the
stiffness of the material 66 preventing collapse of the vessel 52, and
reducing the risk of dislodgement of particles of plaque into the
bloodstream.
The tube 64 allows any gas given off by the setting sleeve material 66
during its solidification to escape to the atmosphere. Once the
solidification reaction is effectively completed, the tube 64 can be
removed by pulling on it and causing it to sever from the sleeve 51 at a
point 69, where it is connected to the sleeve where a frangible thin wall
section may be provided in the wall of the tube for this purpose. It is
contemplated that the catalyst for setting of the material 66 can be
encapsulated and mixed with the base and caused to release from such
encapsulation upon the pressure applied thereto by expansion of the
balloon 50. Another alternative is to introduce the settable material 66,
including mixed catalyst, into the space 63 through the tube 64 after the
sleeve 51 has been manipulated into position.
The invention is not restricted to the slavish imitation of each and every
detail set forth above. Obviously, devices may be provided which change,
eliminate, or add certain specific details without departing from the
scope of the invention.
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