U.S. patent application number 12/286722 was filed with the patent office on 2009-02-12 for use of magnetic implants to treat body tissue structrues.
This patent application is currently assigned to Torax Medical, Inc.. Invention is credited to Jerome Kent Grudem, JR., Chad John Kugler.
Application Number | 20090043148 12/286722 |
Document ID | / |
Family ID | 32738906 |
Filed Date | 2009-02-12 |
United States Patent
Application |
20090043148 |
Kind Code |
A1 |
Kugler; Chad John ; et
al. |
February 12, 2009 |
Use of magnetic implants to treat body tissue structrues
Abstract
Plural (at least two) magnetic devices are implanted in a
patient so that magnetic interaction between those devices modifies
the patient's body in one or more respects (e.g., by modifying the
shape and/or performance of some part of the body). Prior to
implantation, a location in the body may be marked for later
reference during the implantation. The magnetism of one or more of
the magnetic devices may be changed in vivo after implantation. One
or more of the implanted devices may be subsequently removed from
the patient if desired. Use of the magnetic devices inside tissue
conduits (e.g., as a treatment for GERD) is especially considered
by way of illustration.
Inventors: |
Kugler; Chad John; (Andover,
MN) ; Grudem, JR.; Jerome Kent; (Rogers, MN) |
Correspondence
Address: |
ROPES & GRAY LLP
PATENT DOCKETING 39/361, 1211 AVENUE OF THE AMERICAS
NEW YORK
NY
10036-8704
US
|
Assignee: |
Torax Medical, Inc.
|
Family ID: |
32738906 |
Appl. No.: |
12/286722 |
Filed: |
September 30, 2008 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
10612496 |
Jul 1, 2003 |
7445010 |
|
|
12286722 |
|
|
|
|
60444065 |
Jan 29, 2003 |
|
|
|
60457959 |
Mar 25, 2003 |
|
|
|
60465283 |
Apr 23, 2003 |
|
|
|
Current U.S.
Class: |
600/12 |
Current CPC
Class: |
A61N 2/06 20130101; A61F
2210/009 20130101; A61F 5/0079 20130101; A61F 2/0036 20130101 |
Class at
Publication: |
600/12 |
International
Class: |
A61N 2/00 20060101
A61N002/00 |
Claims
1. A method of treating a tissue passage in a patient comprising:
implanting at least two magnetic devices in the passage so that the
devices are positioned for magnetic interaction with one
another.
2. The method defined in claim 1 wherein the magnetic devices
transfer force due to the magnetic interaction to the passage
wall.
3. The method defined in claim 2 wherein each magnetic device
transfers force due to the magnetic interaction to a respective
portion of the passage wall.
4. The method defined in claim 1 wherein the magnetic interaction
is predominantly magnetic attraction.
5. The method defined in claim 1 wherein the magnetic devices are
implanted so that the magnetic interaction between them is
predominantly transverse to a longitudinal axis of the passage.
6. The method defined in claim 1 wherein the magnetic devices are
implanted so that the magnetic interaction between them is across a
lumen of the passage.
7. The method defined in claim 1 wherein the implanting is
performed intraluminally with respect to the passage.
8. The method defined in claim 1 wherein the implanting comprises:
passing at least one of the magnetic devices along a lumen of the
passage; and securing the at least one magnetic device to the
passage wall after the passing has conveyed that device to a
desired location in the passage.
9. The method defined in claim 8 wherein the securing comprises:
penetrating the passage wall with a retaining structure for the at
least one magnetic device.
10. The method defined in claim 1 further comprising: changing the
magnetism of at least one of the magnetic devices in vivo after the
implanting.
11. The method defined in claim 10 wherein the changing is
performed intraluminally with respect to the passage.
12. The method defined in claim 10 wherein the changing is
performed by means that are passed along the inside of the passage
adjacent to the at least one of the magnetic devices.
13. The method defined in claim 1 further comprising: marking a
location in the passage that is to receive at least one of the
magnetic devices prior to the implanting.
14. The method defined in claim 13 wherein the marking is performed
intraluminally with respect to the passage.
15. The method defined in claim 1 further comprising: removing at
least one of the magnetic devices subsequent to the implanting.
16. The method defined in claim 15 wherein the removing is
performed intraluminally with respect to the passage.
17. Apparatus for treating a tissue passage in a patient
comprising: means for implanting at least two magnetic devices in
the passage so that the devices are positioned for magnetic
interaction with one another.
18. The apparatus defined in claim 17 wherein the means for
implanting comprises: means for securing at least one of the
magnetic devices to the passage wall.
19. The apparatus defined in claim 18 wherein the means for
securing comprises: means for causing a portion of the at least one
magnetic device to penetrate the passage wall.
20. The apparatus defined in claim 17 wherein the means for
implanting is configured for intraluminal operation with respect to
the passage to at least some extent.
21. The apparatus defined in claim 17 wherein the means for
implanting is configured to deliver at least one of the magnetic
devices into the passage intraluminally.
22. The apparatus defined in claim 21 wherein the means for
implanting is further configured to secure the at least one of the
magnetic devices to the passage wall intraluminally.
23. The apparatus defined in claim 17 wherein the means for
implanting is configured to implant the magnetic devices at
respective locations on the passage wall that are spaced from one
another around the passage.
24. The apparatus defined in claim 23 wherein the respective
locations are on respective opposite sides of a lumen of the
passage.
25. A system for treating a tissue passage in a patient comprising:
apparatus as defined in claim 17; and means for marking a location
in the passage for use as a reference in subsequent use of the
apparatus.
26. The apparatus defined in claim 17 further comprising: means for
changing the magnetism of at least one of the magnetic devices in
vivo.
27. The apparatus defined in claim 26 wherein the means for
changing is configured for operation intraluminally with respect to
the passage.
28. The apparatus defined in claim 17 further comprising: means for
removing at least one of the magnetic devices from the passage.
29. The apparatus defined in claim 28 wherein the means for
removing is configured for operation intraluminally with respect to
the passage.
30. A method of treating a tissue passage in a patient comprising:
implanting at least two magnetic devices adjacent the passage so
that the devices are positioned for magnetic interaction with one
another.
31. The method defined in claim 30 wherein at least one of the
magnetic devices is embedded in tissue beneath a surface of the
passage wall.
32. The method defined in claim 31 wherein the at least two
magnetic devices comprise a set, and wherein the method further
comprises: implanting a third magnetic device adjacent the passage
at a location that is spaced from the set but so that the third
magnetic device is positioned for magnetic interaction with at
least one of the magnetic devices in the set.
33. Apparatus for treating a tissue passage in a patient
comprising: means for implanting at least two magnetic devices
adjacent the passage so that the devices are positioned for
magnetic interaction with one another.
34. The apparatus defined in claim 33 wherein the means for
implanting is configured to embed at least one of the magnetic
devices in tissue beneath a surface of the passage wall.
35. The apparatus defined in claim 34 wherein the at least two
magnetic devices comprise a set, and wherein the apparatus further
comprises: further means for implanting a third magnetic device
adjacent the passage at a location that is spaced from the set but
so that the third magnetic device is positioned for magnetic
interaction with at least one of the magnetic devices in the set.
Description
[0001] This application claims the benefit of U.S. provisional
patent applications Nos. 60/444,065 (filed Jan. 29, 2003),
60/457,959 (filed Mar. 25, 2003), and 60/465,283 (filed Apr. 23,
2003), all of which are hereby incorporated by reference herein in
their entireties. This is a division of U.S. patent application
Ser. No. 10/612,496 (filed Jul. 1, 2003), which is hereby
incorporated by reference herein in its entirety.
BACKGROUND OF THE INVENTION
[0002] This invention relates to medical apparatus and procedures,
and more particularly to apparatus and methods for treating tubular
or similar body organ tissue structures for such purposes as
strengthening some of their functions, reducing their size or
otherwise modifying their geometry, changing wall tension,
restricting flow, affecting or effecting tissue movement, and/or
the like.
[0003] This invention has many possible applications. More examples
of such applications will be mentioned later in this specification.
Initially, however, it will suffice to discuss the problem of
gastro-esophageal reflux disorder or disease ("GERD") as background
for the invention.
[0004] GERD is a condition in which the sphincter and/or other body
structures at or near the transition between the lower end of the
esophagus and the upper end of the stomach does or do not keep that
passageway closed in the normal way. This can allow material in the
stomach to re-enter the esophagus, which can be uncomfortable for
the patient and, in the long term, can endanger the patient (e.g.,
by causing damage to and/or disease of the esophagus).
[0005] A common cause of GERD is weakness or relaxation of the
sphincter that normally keeps the lower end of the esophagus closed
(the lower esophageal sphincter or LES). Alternatively or in
addition, there may be displacement of other tissue structures
relative to the LES that may make the esophagus-closing mechanism
less effective than it should be.
[0006] Many other similar conditions can exist elsewhere in the
body. For example, a sphincter in the urinary tract can become
weak, resulting in urinary incontinence. The tissue surrounding or
adjacent to any lumen in the body may be in need of an improvement
in tone (i.e., an improvement in muscle tone or analogous to an
improvement in muscle tone). Such an improvement in tone may help
to reduce the size of the lumen or otherwise modify the shape or
geometry of the lumen, strengthen or assist a sphincter associated
with the lumen, and/or otherwise improve the performance of the
lumen. In addition to the improvements in tone described above,
other body lumen improvements may also be desirable. For example,
such improvements may include closure or restriction of a body
lumen to limit or stop the passage of gas, liquid, or solids in the
body lumen (such as the urethra or bladder for incontinence
control) or in a body cavity such as in the stomach or lungs. The
term "passage" may be used herein as a generic term for tubular
tissue structures or lumens and for body cavities.
[0007] In view of the foregoing, it is an object of this invention
to provide apparatus and methods for such purposes as improving the
tone of, strengthening, reinforcing, and/or reducing the size or
otherwise changing the geometry of any of various lumens, organs,
cavities, or similar structures in a patient's body.
SUMMARY OF THE INVENTION
[0008] This and other objects of the invention are accomplished in
accordance with the principles of the invention by apparatus and
methods whereby multiple (at least two) magnetic devices are
implanted in a patient so that magnetic attraction (or repulsion)
between those devices modifies adjacent tissue structures. The
magnetic devices employed in accordance with the invention can be
all actively magnetic devices, or one or more passively magnetic
devices can be used with one or more actively magnetic devices. An
actively magnetic device is a source of a magnetic field. Examples
of actively magnetic devices are permanent magnets and
electromagnets. A passively magnetic device is not itself a
magnetic field source, but it is magnetically responsive to a
magnetic field (e.g., it is magnetically attracted to an actively
magnetic device). An example of a passively magnetic device is a
body of initially unmagnetized ferro-magnetic material. As used
herein, the phrase "magnetic device" generally refers to both
actively and passively magnetic devices. However, it should be
understood that in any system of multiple magnetic devices there
will generally need to be at least one actively magnetic
device.
[0009] Another aspect of the invention relates to methods and
apparatus for marking a location in a patient for use as a
reference during subsequent implanting of magnetic devices.
[0010] Still another aspect of the invention relates to methods and
apparatus for removing a magnetic device that has been implanted in
a patient.
[0011] Yet another aspect of the invention relates to methods and
apparatus for changing the magnetism, in vivo, of at least one
magnetic device that has been implanted in a patient.
[0012] Further features of the invention, its nature and various
advantages will be more apparent from the accompanying drawings and
the following detailed description of the preferred
embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] FIG. 1 is a simplified sectional view of a portion of a
patient's internal anatomy.
[0014] FIG. 2 is similar to FIG. 1, but with the addition of
illustrative structures in accordance with the invention.
[0015] FIG. 3 is a simplified, partial, sectional view of
illustrative apparatus in accordance with the invention.
[0016] FIG. 4 is a simplified, partly elevational and partly block
diagram depiction of illustrative apparatus in accordance with the
invention.
[0017] FIG. 5 is similar to FIG. 3 for another illustrative
embodiment of the invention.
[0018] FIG. 6 is a simplified perspective view, partly in section,
of an illustrative embodiment of an implantable magnetic device in
accordance with the invention.
[0019] FIG. 7 is a simplified perspective view of another
illustrative embodiment of an implantable magnetic device in
accordance with the invention.
[0020] FIGS. 8-10 are similar to FIG. 7 for other illustrative
embodiments of implantable devices in accordance with the
invention.
[0021] FIG. 11 is similar to FIG. 5 for yet another illustrative
embodiment of the invention.
[0022] FIG. 12 shows a relatively early stage in use of the FIG. 11
apparatus in a patient's anatomy like that shown in FIG. 1 in
accordance with the invention.
[0023] FIGS. 13, 14, 17, 18, and 19 are each similar to FIG. 11,
but show successive stages in operation of the FIG. 11 apparatus in
accordance with the invention.
[0024] FIG. 15 is a simplified, partly sectional, perspective view
showing a relatively early stage in implanting an illustrative
magnetic device in a patient's tissue in accordance with the
invention.
[0025] FIG. 16 is similar to FIG. 15 for a later stage in
implanting the magnetic device in accordance with the
invention.
[0026] FIGS. 20-22 are views similar to FIG. 14 for still more
illustrative embodiments of apparatus in accordance with the
invention.
[0027] FIG. 23 is a view similar to FIG. 11 for yet another
illustrative embodiment of apparatus in accordance with the
invention.
[0028] FIG. 24 is a view similar to FIG. 23 for still another
illustrative embodiment of apparatus in accordance with the
invention.
[0029] FIG. 25 shows a later stage in use of the FIG. 24
apparatus.
[0030] FIG. 26 is a simplified, partial, elevational view (partly
in section) of an illustrative embodiment of still more apparatus
in accordance with the invention.
[0031] FIG. 27 is a view similar to FIG. 12 showing use of the FIG.
26 apparatus in accordance with the invention.
[0032] FIG. 28 is a simplified, partial, perspective view (partly
in section) of still more illustrative apparatus in accordance with
the invention.
[0033] FIG. 29 is similar to FIG. 27 showing use of the FIG. 28
apparatus in accordance with the invention.
[0034] FIGS. 30-33 are views similar to FIGS. 8-10 for still more
illustrative embodiments of implantable devices in accordance with
the invention.
[0035] FIG. 34 is a simplified, partial, elevational view (partly
in section) of an illustrative embodiment of still more apparatus
in accordance with the invention.
[0036] FIGS. 35-39 are views similar to FIG. 29 showing successive
stages in use of the FIG. 34 apparatus in accordance with the
invention.
[0037] FIG. 40 is another view similar to FIG. 39 showing another
illustrative embodiment of apparatus in accordance with the
invention.
[0038] FIG. 41 is another view similar to FIG. 40 showing an
illustrative embodiment of still more apparatus in accordance with
the invention.
[0039] FIG. 42 is a simplified sectional view of another
illustrative embodiment of a magnetic device in accordance with the
invention.
[0040] FIG. 43 is a simplified perspective view of an illustrative
retention structure that can be used, for example, with magnetic
devices of the type shown in FIG. 42 in accordance with the
invention.
[0041] FIG. 44 is a simplified view, partly in section,
illustrating use of elements like those shown in FIGS. 42 and 43 in
accordance with the invention.
[0042] FIG. 45 is a simplified view, partly in section, showing
illustrative apparatus for delivering and implanting elements like
those shown in FIGS. 42 and 43 in accordance with the
invention.
[0043] FIG. 46 is a simplified view, partly in section, showing an
early stage in use of the FIG. 45 apparatus in accordance with the
invention.
[0044] FIG. 47 is similar to FIG. 46, but shows a later stage in
use of the apparatus.
[0045] FIG. 48 is similar to FIG. 47, but shows a still later stage
in use of the apparatus.
[0046] FIG. 49 is again similar to FIG. 48, but shows the end
result produced by use of the apparatus (which has now been
withdrawn from the patient).
[0047] FIG. 50 is a simplified sectional view (taken generally
along the line 50-50 in FIG. 51) showing an illustrative
implantation of magnetic devices in a patient in accordance with
the invention.
[0048] FIG. 51 is another simplified sectional view taken generally
along the line 51-51 in FIG. 50.
[0049] FIG. 52 is similar to FIG. 50, but shows a different
operating condition of what is shown in FIG. 50. (FIG. 52 is taken
generally along the line 52-52 in FIG. 53.)
[0050] FIG. 53 is another simplified sectional view taken generally
along the line 53-53 in FIG. 52.
[0051] FIG. 54 is a view similar to FIG. 50, but for another
illustrative implantation of magnetic devices in a patient in
accordance with the invention. (FIG. 54 is taken generally along
the line 54-54 in FIG. 55.)
[0052] FIG. 55 is another simplified sectional view taken generally
along the line 55-55 in FIG. 54.
[0053] FIG. 56 is similar to FIG. 52, but for the embodiment shown
in FIGS. 54 and 55. (FIG. 56 is taken generally along the line
56-56 in FIG. 57.)
[0054] FIG. 57 is another simplified sectional view taken generally
along the line 57-57 in FIG. 56.
[0055] FIG. 58 is a simplified, partial, elevational view (partly
schematic in nature) showing still another illustrative
implantation of magnetic devices in a patient in accordance with
the invention.
[0056] FIG. 59 is a simplified sectional view of yet another
illustrative embodiment of a magnetic device in accordance with the
invention.
[0057] FIG. 60 is a simplified elevational view of illustrative
apparatus that can be for implanting in a patient magnetic devices
of the type shown in FIG. 59, for example, in accordance with the
invention.
[0058] FIGS. 61-64 are similar to FIGS. 50-53, respectively, for
yet another illustrative implantation of magnetic devices in a
patient in accordance with the invention. (FIG. 61 is taken
generally along the line 61-61 in FIG. 62; FIG. 62 is taken
generally along the line 62-62 in FIG. 61; FIG. 63 is taken
generally along the line 63-63 in FIG. 64; and FIG. 64 is taken
generally along the line 64-64 in FIG. 63.
[0059] FIG. 65 is similar to FIG. 50 for still another illustrative
implantation of magnetic devices in a patient in accordance with
the invention.
[0060] FIG. 66 is again similar to FIG. 50 for yet another
illustrative implantation of magnetic devices in a patient in
accordance with the invention.
[0061] FIG. 67 is once again similar to FIG. 50 for still another
illustrative implantation of magnetic devices in a patient in
accordance with the invention.
[0062] FIG. 68 is again generally similar to FIG. 50 showing yet
another illustrative implantation of magnetic devices in a patient
in accordance with the invention.
[0063] FIG. 69 is a simplified sectional view showing another
embodiment of illustrative apparatus for implanting magnetic
devices in a patient in accordance with the invention.
[0064] FIG. 70 is another simplified sectional view showing the end
result of an implantation as shown in FIG. 69.
[0065] FIG. 71 is a view similar to FIG. 70, but showing another
illustrative type of implantation of magnetic devices in accordance
with the invention.
[0066] FIG. 72 is a simplified, partial, sectional view showing an
illustrative embodiment of apparatus for implanting magnetic
devices of, for example, the type shown in FIG. 71 in accordance
with the invention.
[0067] FIG. 73 is a view similar to FIG. 72 showing a later stage
in use of the apparatus shown in FIG. 72 in accordance with the
invention.
[0068] FIG. 74 is a simplified, partial, sectional view of another
illustrative embodiment of apparatus in accordance with the
invention.
[0069] FIG. 75 shows a later stage in use of the apparatus shown in
FIG. 74 in accordance with the invention.
[0070] FIG. 76 is a simplified sectional view (taken generally
along the line 76-76 in FIG. 77) showing another illustrative
implantation of magnetic devices in a patient in accordance with
the invention.
[0071] FIG. 77 is another simplified sectional view taken generally
along the line 77-77 in FIG. 76.
[0072] FIG. 78 is a view similar to FIG. 76, but for yet another
illustrative implantation of magnetic devices in a patient in
accordance with the invention. (FIG. 78 is taken generally along
the line 78-78 in FIG. 79).
[0073] FIG. 79 is another simplified sectional view taken generally
along the line 79-79 in FIG. 78.
[0074] FIG. 80 is a simplified elevational view of another
illustrative embodiment of an implantable magnetic device in
accordance with the invention.
[0075] FIG. 81 is a simplified perspective view of the magnetic
device shown in FIG. 80.
DETAILED DESCRIPTION
[0076] As in the case of the above background section, this
detailed description will illustrate the invention initially by
discussing application of the invention to the treatment of GERD.
Later, some of the invention's other possible uses will be
discussed.
[0077] The lower part of a patient's esophagus 10 and adjacent
tissue structures are shown in FIG. 1. It will be understood that
this and other anatomical depictions herein are generally greatly
simplified. The same is true for the anatomical descriptions
herein, both before and after treatments in accordance with this
invention. Many anatomical structures and functions are in fact
quite complex, to the point where they may not even be fully
understood. For example, it may be convenient herein to say that
the esophagus is "open" or "closed" under certain conditions
(either before or after treatment in accordance with the
invention), when in fact the esophagus may be only partly open when
said to be "open", only partly closed (or still partly openable
without separating the magnetic devices as described below) when
said to be "closed", etc. It will therefore be understood that
words like "open" and "close" and other terms and descriptions
employed herein are used in a simplified (sometimes relative) sense
to provide a general indication of how various anatomical
structures operate, both before and after treatment in accordance
with the invention.
[0078] In addition to esophagus 10, FIG. 1 shows a portion of the
patient's diaphragm 20 (through which the esophagus passes), the
upper part of the stomach 30, and the lower esophageal sphincter
40, which is just above the opening into the stomach and normally
close to the diaphragm. The lower part of the esophagus is normally
closed by sphincter 40, perhaps with some help from the adjacent
diaphragm structure 20. Anything swallowed passes down esophagus
10, opening sphincter 40, and entering stomach 30. The esophagus
then normally closes again. Normal pressures in stomach 30 should
not cause sphincter 40 to open. But higher than normal pressures in
the stomach do cause sphincter 40 to open and allow material (e.g.,
gas) to escape from the stomach and exit via the esophagus. In a
patient with GERD, however, sphincter 40 and/or adjacent structures
do not resist normal pressure in the stomach, and so material
(e.g., gas or liquids) from the stomach can enter the esophagus and
cause discomfort and potentially serious disease.
[0079] FIG. 2 shows the end result of treatment of a patient for
GERD in accordance with an illustrative embodiment of the
invention. As shown in FIG. 2, two magnetic devices 100a and 100b
have been implanted in the patient's esophagus in the vicinity of
esophageal sphincter 40. At least one of devices 100 is actively
magnetic. As mentioned earlier, an actively magnetic device (e.g.,
a permanent magnet or an electromagnet) is a source of a magnetic
field. The other of devices 100 may be either actively magnetic or
passively magnetic (e.g., a body of initially unmagnetized
ferro-magnetic material). Thus the phrase "magnetic device"
generally refers to both actively and passively magnetic devices.
However, it will be understood that in any system of multiple
magnetic devices there should be at least one actively magnetic
device.
[0080] In the particular embodiment shown in FIG. 2 magnetic
devices 100a and 100b are implanted in esophagus 10 so that they
magnetically attract one another and help to hold the esophagus
closed in their vicinity. There are many ways that devices 100 can
be implanted, as will be illustrated later in this specification.
The primary purpose of the present discussion is to consider
various preferred aspects of the end result.
[0081] In the illustrative embodiment shown in FIG. 2 each of
devices 100a and 100b is implanted on a respective diametrically
opposite side of the esophageal lumen. (As will be considered in
greater detail in connection with later FIGS., there may be more
than one such "set" of magnetic devices 100 implanted in the
patient. For example, such other "sets" may be implanted at some
longitudinal distance along the esophagus from the first set. Many
other arrangements of multiple sets of implanted magnetic devices
100 are also possible, as will be further illustrated later in this
specification.) The preferred axial location for devices 100 along
the longitudinal axis of the esophagus is adjacent lower esophageal
sphincter 40. Devices 100 are implanted on or in the inner wall
surface of the esophageal lumen in this embodiment. A possible
advantage of this type of surface-implanting is that there is then
no tissue between magnetic devices 100a and 100b when those devices
are able to be pulled together (as shown in FIG. 2) by the magnetic
attraction between them. This tends to give better fore-knowledge
of the end-point magnetic attraction between devices 100. Magnetic
attraction drops off rapidly as the distance between devices 100
increases. Tissue thicknesses can vary. If one or more tissue
thicknesses are between devices 100 when they are closest together,
it can be more difficult to predict how strong the end-point
magnetic attraction will be. But if there is no tissue between
devices 100 when they are closest together in the patient, the
magnitude of the end-point magnetic attraction should be the same
as when the devices are outside the patient prior to being
implanted. In other words, the in vivo end-point magnetic
attraction can be more easily designed into the devices if no
variable tissue thickness comes between those devices when they are
closest together in vivo.
[0082] The strength of the magnetic attraction between devices 100a
and 100b can be any amount that is helpful to keep esophagus 10 at
least partly closed in the absence of material (e.g., food or
liquid) moving down the esophagus or in the absence of higher than
normal stomach pressure that should produce some escape of material
(e.g., gas) up the esophagus. For example, the end-point magnetic
attraction between devices 100a and 100b may be in the range from
about 10 g to about 500 g of force. The amount of force thus
employed may depend on the clinical application of the technology,
various clinical applications being mentioned throughout this
specification.
[0083] Many different securing techniques can be used for magnetic
devices 100a and 100b. Alternatives will be discussed later in this
specification. But for present purposes it will suffice to note
that FIG. 2 shows that each of devices 100a and 100b has two
sharply pointed prongs 110 that extend out from the rear of the
associated device in directions that diverge from one another away
from the remaining, main body of the associated device. In the
illustrative embodiment shown in FIG. 2 each of prongs 110 is made
of metal, preferably a highly elastic, resilient metal such as
nitinol. In this embodiment prongs 110 are resiliently biased to
assume the positions shown in FIG. 2. The prongs 110 of each device
100 preferably penetrate the tissue of the esophagus, perhaps first
entering that tissue relatively parallel to one another, and then
spreading apart in or beyond the tissue to secure the device to the
tissue and resist removal of the device from the tissue. The free
ends of prongs 110 are preferably sharpened to facilitate this
penetration of the tissue by the prongs. FIG. 2 shows the tissue as
essentially a two-layer structure. But the tissue structure may in
fact have even more layers than this, depending to some extent on
how closely one analyzes the structure. Prongs 110 may penetrate
this tissue structure to any desired degree. In the embodiment
shown in FIG. 2 prongs 110 are shown passing through a superficial
inner layer of the tissue structure and entering a more muscular
(and therefore stronger) outer layer of the tissue. It is desirable
for the attachment structure to engage some relatively strong
tissue structure to ensure good retention of devices 100. An
alternative to what is shown in FIG. 2 (discussed in more detail
later in this specification) is to have the retention structure
such as prongs 110 pass almost all the way through the associated
tissue structure.
[0084] Devices 100 are designed so that they will be tolerated by
the patient after they have been implanted. For example, devices
100 are designed so that they will be basically inert in the
patient. In this context "inert" just means that devices 100 should
not be destructively attacked by anything in the patient's body
that they will come in contact with. Inert also means that devices
100 should not stimulate a rejection mechanism by the patient's
body. Moreover, devices 100 do not release anything that would be
harmful to the patient (although they may be medicated to release
one or more drugs into the patient). Thus at least the material or
materials of all external surfaces of devices 100 are preferably
biocompatible. Some of the materials used inside of devices may not
be biocompatible, but any such materials are enclosed or
encapsulated using materials that are biocompatible.
[0085] Reverting again to the operation of the illustrative
embodiment shown in FIG. 2, after devices 100a and 100b have been
installed in the patient as shown in FIG. 2, these devices
magnetically attract one another across the esophagus and help
sphincter 40 and/or the esophagus remain substantially closed at
the location of sphincter 40 or adjacent esophagus. When the
patient swallows something relatively solid, devices 100a and 100b
may move apart from one another and thereby allow the swallowed
material to pass down the esophagus, through the opened sphincter
40, and into stomach 30. Thereafter, the magnetic attraction
between devices 100 pulls them toward one another again, thus
helping to hold the esophagus at least partly closed at or adjacent
to sphincter 40. Swallowing liquid may not cause devices 100 to
separate. Instead, the tissue around the magnets may open
sufficiently to allow the swallowed liquid to pass without devices
100 separating. Normal pressure in the stomach is not high enough
to completely open sphincter 40, reinforced by the mutual magnetic
attraction of devices 100. Higher than normal pressure in the
stomach, however, is able to open sphincter 40 and separate devices
100 from one another. This allows such higher than normal stomach
pressure to be relieved by a flow of material up the esophagus.
Again, after such a pressure-relieving back-flow of material, the
magnetic attraction between devices 100 helps to reclose sphincter
40. It is also possible that magnets 100a and 100b will remain
closed, but surrounding tissue may open to allow gas in the stomach
to pass back through the esophagus under certain higher pressure
conditions in the stomach.
[0086] In connection with what is said above about implanted
magnetic devices 100 being beneficial even when they remain
together but allow adjacent portions of the esophagus to open under
certain conditions, the following discussion may be helpful.
Positioning magnets within the esophagus can increase lower
esophageal sphincter ("LES") tone by a factor directly related to
the geometry obtained. In the case of two magnets positioned
180.degree. apart, the normally round cross section of the LES is
pinched in the middle, creating two separate lobes that approximate
two separate cylinders. Each of these lobes comprises approximately
half the original esophagus circumference and half the original
esophagus diameter. This reduction in circumference and diameter
results in an increase in LES tone. This increase in tone (and the
effect of stomach pressure on these lobes) may be described in
general, theoretical terms in equations found in the textbook,
Shigley et al., Mechanical Engineering Design, Fifth Edition, 1989,
McGraw-Hill, Inc., New York, pp. 58-60. This text suggests that a
reduction of a thin-walled conduit diameter by a factor of two will
double the strength of the conduit wall to resist an internally
applied pressure. In the case of the LES, this duplication in
strength may result in an increase in tone and an increase in the
pressure barrier to stomach acid reflux.
[0087] Although not expressly mentioned earlier, it should be
apparent from what has been said that any actively magnetic
material in either of devices 100 is magnetically polarized
relative to the physical structure of the device so that when the
devices are implanted in the patient as shown in FIG. 2, devices
100 will magnetically attract one another across the lumen of the
esophagus. (In other embodiments and/or applications of the
invention the magnetic polarization may be such as to cause devices
like 100a and 100b to magnetically repel one another.)
[0088] FIG. 3 shows a portion of illustrative apparatus in
accordance with the invention for implanting devices like 100 in a
patient's esophagus as shown in FIG. 2. Again, many variations of
and alternatives to what is shown in FIG. 3 are possible. Some of
these variations and alternatives will be discussed later in this
specification. But what is shown in FIG. 3 will serve as a useful
starting point.
[0089] FIG. 3 shows that each of devices 100a and 100b may include
a disc-like main body 102. A short post or stud 104 may project
substantially perpendicularly out from the center of one of the
major, approximately planar surfaces of main body 102. Prongs 110
extend from opposite sides of each stud 104. For example, the
prongs 110 of each device 100 may be respective opposite end
portions of a single wire or wire-like member that passes through
the stud 104 of that device transverse to the longitudinal axis of
the stud. The magnetic material of each device 100 is preferably at
least primarily the main body 102 of that device (or is contained
or encapsulated within the main body 102 of that device). Again,
any actively magnetic material in either device 100 is magnetically
polarized so that at least after the devices have been implanted in
a patient, they will magnetically attract one another.
[0090] In addition to showing illustrative devices 100 in a bit
more detail, FIG. 3 shows a relatively distal portion of delivery
system apparatus 200 for use in implanting devices 100 into a
patient's esophagus as shown in FIG. 2. More of delivery system 200
is shown in FIG. 4. The portion of delivery system 200 that is
shown in FIG. 3 includes a body structure 210 secured to a distal
portion of an elongated catheter or catheter-like structure 220. At
or adjacent its proximal end catheter 220 is attached to a system
of control elements 230, 240, 250, 260, and 270 (see FIG. 4).
Catheter structure 220 is preferably at least long enough so that
distal portion 210 can be introduced into the patient through the
patient's mouth and passed down esophagus 10 to the vicinity of
sphincter 40, while elements 230, 240, 250, 260, and 270 remain
outside the patient. Overall longitudinal placement of distal
portion 210 in the patient (i.e., adjacent sphincter 40) is
controlled by control element 230 acting through catheter 220. For
example, distal portion 210 may be pushed distally into the patient
or pulled proximally out of the patient by moving control element
230 toward or away from the patient's mouth. Catheter structure 220
(although somewhat transversely flexible) acts as a longitudinally
extending mechanical connection between elements 210 and 230.
[0091] Returning to FIG. 3, each of devices 100a and 100b is
initially loaded in a respective one of recesses 212a and 212b in
the side wall of distal portion 210. Each of recesses 212 extends
substantially radially with respect to a longitudinal axis of
distal portion 210. Recesses 212 are on diametrically opposite
sides of distal portion 210. The cross sectional shape and size of
each recess 212 are approximately the same as the outer perimeter
shape and size of the main body 102 of the device 100 initially
loaded in that recess. These shapes and sizes are chosen so that
each device 100 will have a relatively tight, but still slidable,
fit within the associated recess 212.
[0092] At one of its ends, each recess 212 opens to the outer
surface of distal portion 210. At its other end, each recess 212
communicates with an associated lumen 214a or 214b for liquid or
gas (generically fluid).
[0093] While each device 100 is disposed in its associated recess
212, the prongs 110 of that device are resiliently deflected
inwardly by the side wall of the recess. This deflection makes the
prongs 110 of each device 100 substantially parallel to one another
and pointing radially outwardly relative to a central longitudinal
axis of distal portion 210.
[0094] On the side surface of distal portion 210, the opening of
each recess 212 is surrounded by an inflatable balloon structure
216a or 216b. Balloon structures 216 do not have to completely
surround each recess 212, but it is desirable for each balloon
structure 216 to be relatively symmetrical about the associated
recess 212 opening. The interior of each balloon structure 216 is
in fluid communication with a respective one of inflation lumens
218a and 218b. Each balloon structure 216 can be inflated by
supplying pressurized fluid to that balloon structure via the
associated inflation lumen 218. After such inflation, a balloon
structure 216 can be deflated by allowing the inflation fluid to
flow back out of the balloon via the associated lumen 218.
[0095] The purpose of each balloon structure 216 is to press distal
portion 210 against the opposite side of the esophagus, and also to
somewhat temporarily enlarge or distend the esophagus and annularly
stretch its tissue adjacent distal portion 210. For example, by
inflating balloon structure 216b when distal portion 210 is at the
desired location longitudinally along the esophagus, the radially
outer opening of recess 212a is pushed against the side of the
inner surface of the esophagus diametrically opposite inflated
balloon structure 216b. As a result, the tissue of the esophagus is
somewhat stretched across the opening of recess 212a. Pressurized
fluid is then applied to lumen 214a, which drives device 100a out
of recess 212a and into the immediately adjacent portion of the
wall of the esophagus. In particular, the prongs 110 of device 100a
first begin to exit recess 212a and enter the esophagus wall tissue
substantially parallel to one another. As more of the length of
prongs 110 extends from recess 212a, the prongs are gradually less
constrained by the wall of the recess. Prongs 110 are therefore
increasingly able to deflect away from one another as they
penetrate farther into the esophagus wall tissue. Ultimately device
100a is pushed completely out of recess 212a and the prongs 110 of
that device are fully embedded in the wall of the esophagus in the
spread-apart condition shown in FIG. 2. (Of course, at this point
the condition of the patient differs from what is shown in FIG. 2
because the distal portion of delivery apparatus 200 is still in
the patient's esophagus with balloon structure 216b still inflated
and device 100b not yet driven out of the delivery apparatus.)
[0096] The next steps are to deflate balloon structure 216b via
lumen 218b and to then inflate balloon structure 216a via lumen
218a. This pushes distal portion 210 toward the opposite side of
the patient's esophagus, causing the tissue of that side of the
esophagus to be somewhat stretched over the opening of recess 212b.
Device 100b is then driven out of recess 212b by the application of
pressurized fluid to lumen 214b. Device 100b deploys from recess
212b in the same way that has been described above for the
deployment of device 100a from recess 212a.
[0097] After device 100b has been deployed, balloon structure 216a
is deflated via lumen 218a and the distal portion of delivery
system 200 is pulled out of the patient via the patient's mouth.
The condition of the patient is now as shown in FIG. 2.
[0098] Returning to FIG. 4, lateral placement control 1 (element
240) controls the inflation and deflation of balloon structure
216a, lateral placement control 2 (element 250) controls the
inflation and deflation of balloon structure 216b, magnetic device
1 ejection control 260 controls the ejection of device 100a from
recess 212a (in this embodiment, via pressurized fluid supplied to
recess 212a behind device 100a), and magnetic device 2 ejection
control 270 similarly controls ejection of device 100b from recess
212b. Because in this embodiment pressurized fluid is used to
effect the various functions controlled by elements 240, 250, 260,
and 270, lumens for such fluid may extend from each of these
elements, through catheter structure 220, to the relevant parts of
distal portion 210. For example, inflation lumen 218a may extend
between element 240 and balloon structure 216a, and pressurized
fluid lumen 214a may extend between recess 212a and element 260.
One or more sources of pressurized fluid may be in or connected to
control elements 240, 250, 260, and 270, and each of these elements
typically includes a controllable valve for allowing pressurized
fluid to selectively pass into (or out of) the appropriate portion
of the remainder of the apparatus.
[0099] Although shown separately in FIG. 4, all or various ones of
elements 230, 240, 250, 260, and 270 may be integrated together.
Also, some or all of the various control elements may be
operationally interlocked and/or sequenced to make sure that they
are operable only in a certain sequence. For example, such
interlocking may prevent simultaneous operation of elements 240 and
250. Similarly, such interlocking may prevent element 270 from
being operated before element 240 has been operated, and may
further prevent element 260 from being operated before element 250
has been operated. Some or all of the operating sequence of
delivery device 200 may be automated, if desired.
[0100] FIG. 5 shows an alternative embodiment of the portion of
delivery apparatus 200 that is shown in FIG. 3. The only
significant difference between what is shown in FIG. 5 and what is
shown in FIG. 3 is the following. In FIG. 3 the main body 102 of
each of devices 100 fits sufficiently closely in the associated
recess 212 that pressurized fluid in the recess behind the device
can be used to eject the device from the recess. In FIG. 5 rubber
or rubber-like O-ring or a disk 103 is positioned behind each
device 100 in the associated recess 212 to help provide a seal for
pressurized fluid that will be injected into the recess. This helps
ensure sufficient fluid pressure build-up in each recess 212 to
drive the associated device 100 from that recess. In other respects
the FIG. 5 alternative can be constructed and operated as described
above for FIG. 3, and what is shown in FIG. 5 can be the distal
portion 210 of the more complete delivery system 200 shown in FIG.
4.
[0101] FIG. 6 shows some more details about one illustrative
construction of a representative magnetic device 100 of the type
described above. This embodiment includes disk-shaped permanent
magnet 105 embedded in an external structural shell 107. The magnet
can be made of any material capable of producing a magnetic field.
Because of their superior field strength, rare earth magnets are
particularly preferred. Examples include Alnico
(aluminum/nickel/cobalt), SmCo (samarium/cobalt), and NdFeB
(neodymium/iron/boron). The force exerted by the magnet depends on
such factors as the material of the magnet, the amount of magnetic
material, the dimensions of the magnet, etc. As noted earlier in
this specification, the required magnet strength will depend on the
intended application. For example, for treating the esophagus as
described above, the magnetic force should be sufficient to help
keep the esophagus closed except when material is being swallowed
or when there is higher than normal pressure in the stomach. Magnet
105 may be encapsulated in the structural shell 107 by welding,
potting, injection molding, press fitting, or any other means of
surrounding the magnet with a suitable material.
[0102] Suitable materials for external shell 107 are preferably
non-porous, biocompatible, biostable, corrosion resistant, and
strong enough to withstand in vivo loads. Examples of suitable
materials include (but are not limited to) known implantable metals
such as stainless steel or titanium, high-density polymers such as
parylene or ultra-high molecular weight polyethylene, or materials
made from non-metallic minerals such as ceramic or glass.
[0103] FIG. 7 shows an embodiment of the magnet housing 107 with an
added feature that includes through-holes 109 located around the
circumference that are designed to facilitate more permanent
attachment to the esophagus wall via tissue in-growth.
[0104] FIG. 8 is similar to FIG. 7, but shows an alternative
embodiment of the magnet housing 107 with a mesh 111 fixed to or
formed as part of the surface that will be in closest and most
extensive contact with the wall of the esophagus in a patient. Mesh
111 can be made from any known implantable metallic or polymeric
material. Preferred materials include titanium, stainless steel,
nitinol, polyester, Dacron, and Teflon. Tissue in-growth into mesh
111 increases the permanence with which device 100 is implanted in
the patient.
[0105] FIG. 9 shows magnet housing 107 with permanently fixed
retentive prongs or struts 110. Wire-like struts 110 have free ends
113 that are mechanically, chemically, or electro-chemically
sharpened. Struts 110 are designed to secure magnetic device 100 to
the esophageal wall. Struts 110 can be made of any implantable
structural material. Preferred materials include super-elastic
metallic alloys such as nitinol. Struts 110 may be fixed to magnet
housing 107 via methods that include (but are not limited to)
interference fit, adhesive, solder, or braze between components.
FIG. 9 shows two oppositely extending struts 110, but additional
struts may be included if desired.
[0106] FIG. 10 is similar to FIG. 9, but shows an alternative
embodiment of magnet housing 107 with retention struts 110 that are
laser cut, electro-discharge machined, water jet cut, or
photochemically etched from a sheet of metallic material. The
retention struts are fixed to magnet housing 107 via interference
fit, adhesive, solder, or braze between components.
[0107] FIG. 11 shows an alternative embodiment of the distal
portion 210 of deployment apparatus generally similar to that shown
in FIGS. 3-5 and described above. The major difference between
distal portion 210 in FIG. 11 and distal portion 210 in FIGS. 3 and
5 is that in FIG. 11 magnetic devices 100a and 100b are ejected
from recesses 212a and 212b by mechanical means rather than by
pressurized fluid as in FIGS. 3 and 5. In other respects the
structure shown in FIG. 11 can be the same as the structure shown
in FIGS. 3 and 5, and the structure shown in FIG. 11 can be used as
the distal portion of a delivery system like that shown in FIG. 4.
In order to adapt the FIG. 4 system for a distal portion as shown
in FIG. 11, control elements 260 and 270 may be made mechanical
actuators rather than pressurized fluid actuators. The lumens 218a
and 218b that supply pressurized fluid to balloon structures 216a
and 216b are not shown in FIG. 11 to simplify the drawing. The
construction and operation of the FIG. 11 embodiment will now be
described with reference to FIG. 11 and related FIGS. 12-19. It
will not be necessary to exhaustively describe all details of these
FIGS. because some of those details have already been described in
connection with other embodiments.
[0108] FIG. 11 shows the initial condition of this embodiment of
distal portion 210. Magnetic devices 210a and 210b are loaded in
recesses 212a and 212b, respectively; balloon structures 216a and
216b are both deflated; and deployment wedges 280a and 280b are
both below the level of recesses 212. Each of wedges 280 is a
relatively thin triangular plate that can be pulled upwardly by an
associated wedge pull wire 282a or 282b. When thus pulled upward,
each wedge 280 can travel across the associated recess 212 because
the side wall of each recess is open on both sides where the wedge
will pass through. These slot-like openings in the side walls of
each recess are either too narrow to permit escape of prongs 110 or
prongs 110 are not aligned with those openings in order to prevent
escape of the prongs.
[0109] FIG. 12 shows positioning of distal portion 210 (of the type
shown in FIG. 11) in a patient's esophagus 10 adjacent lower
esophageal sphincter 40. The apparatus is now ready for further
operation to implant magnetic devices 100a and 100b into the
esophageal wall. The succession of operations performed to achieve
this result are illustrated by the next several FIGS. and described
below (although the presence of the esophageal tissue around the
apparatus is not shown in all of these next FIGS.).
[0110] FIG. 13 shows inflation of left side esophagus distention
balloon structure 216a. This pushes the opposite (right) side of
distal portion 210 more firmly against the opposite (right) side of
the esophagus and ensures that the tissue on that opposite (right)
side of the esophagus is stretched over the open end of right side
recess 212b.
[0111] In FIG. 14 balloon structure 216a is still inflated and
right side deployment wedge 280b has been pulled up into recess
212b by proximal retraction of the associated right wedge pull wire
282b. Movement of deployment wedge 280b into recess 212b causes the
inclined surface of the wedge to cam or wedge right side magnetic
device 100b out of recess 212b and into the adjacent wall of the
esophagus. Initial outward movement of magnetic device 100b in
response to the above-described movement of deployment wedge 280b
is shown in FIG. 15. During this initial movement, the free end
portions of prongs 110 remain relatively parallel to one another
(still constrained by recess 212b). Prongs 110 therefore at least
begin to penetrate esophageal tissue 10 relatively parallel to one
another. Final outward movement of magnetic device 100b in response
to the above-described movement of deployment wedge 280b is
illustrated by FIG. 16. Now prongs 110 are no longer constrained by
recess 212b. Prongs 110 are therefore free to resiliently deflect
toward their relatively relaxed positions in which they extend in
opposite directions from one another into (and possibly even
through) esophageal tissue 10. This "splayed apart" condition of
prongs 110 in (and possibly through) tissue 10 secures magnetic
device 100b to esophageal tissue 10.
[0112] After right side magnetic device 100b has been deployed as
described above, left side esophagus distention balloon structure
216a is deflated and right side esophagus distention balloon
structure 216b is inflated as shown in FIG. 17. This pushes distal
portion 210 more firmly against the left side of the esophagus and
ensures that the tissue of the esophagus is stretched across the
entrance to left side recess 212a.
[0113] As shown in FIG. 18, the next step is to raise left side
deployment wedge 280a by pulling proximally on left side wedge pull
wire 282a. This causes left side deployment wedge 280a to enter
recess 212a, thereby driving left side magnetic device 100a out of
that recess and into the adjacent wall of the esophagus (in the
same way that right side deployment wedge 280b earlier drove right
side magnetic device 212b out of recess 212b and into the tissue on
the opposite side of the esophagus).
[0114] After left side magnetic device 100a has been deployed,
balloon structure 216b is deflated as shown in FIG. 19. The entire
apparatus 200 (exclusive of magnetic devices 100) can now be
removed from the patient, and the final condition of the patient's
esophagus will be as shown in FIG. 2.
[0115] It will be understood that the order in which devices 100a
and 100b are deployed is entirely a matter of choice. The
particular order shown and described above is merely exemplary.
[0116] FIG. 20 shows another illustrative embodiment of the distal
portion 210 of illustrative deployment system 200. In this
embodiment each of recesses 212a and 212b contains an inflatable
structure 215a or 215b behind the magnetic device 100 in that
recess. Each inflatable structure 215 is in fluid communication
with a respective one of inflation lumens 214a and 214b (like the
similarly numbered lumens 214a and 214b in FIG. 3 or FIG. 5). When
it is desired to eject one of magnetic devices 100 from the
associated recess 212, the inflatable structure 215 behind that
device is inflated by supplying pressurized fluid to the lumen 214
connected to that inflatable structure. This causes the inflatable
structure 215 to inflate, thereby forcing the associated magnetic
structure 100 out of the associated recess 212. For example, FIG.
20 shows balloon structure 216a inflated, as is appropriate in
preparation for ejection of magnetic device 100b. And FIG. 20 shows
inflation of inflatable structure 215b and resulting ejection of
magnetic device 100b. It will be understood that what is shown in
FIG. 20 can be used as the distal portion of a more complete
deployment system like that shown in FIG. 4. It will also be
understood that FIG. 20 omits (to avoid complicating the drawing)
the lumens 218 (e.g., FIG. 3 or FIG. 5) that are typically provided
for inflation of balloon structures 216. Examples of suitable
materials for inflatable members 215 include (but are not limited
to) silicone, PET, Pebax, nylon, latex, and polyurethane.
[0117] FIG. 21 shows another illustrative embodiment of distal
portion 210 of illustrative deployment system 200. In this
embodiment, a pre-stressed compression coil spring 290a or 290b is
disposed behind each magnetic device 100a or 100b, respectively.
Each spring 290 is releasably held in its compressed condition by a
structure that includes release wire 292a or 292b. When it is
desired to release a spring 290 so that it can eject the associated
magnetic device, the release wire 292 for that spring is pulled in
the proximal direction. For example, FIG. 21 shows the elements
290a and 292a (on the left) prior to proximal retraction of release
wire 292a. Magnetic device 100a is therefore undisturbed in recess
212a. On the right, however, release wire 292b has been proximally
retracted. Spring 290b has therefore been released to expand and
drive magnetic device 100b out of recess 212b. Any of a wide range
of spring and release mechanisms can be used in embodiments of the
general type illustrated by FIG. 21. Again, the lumens for
inflating balloon structures 216 have not been shown in FIG. 21 to
simplify the drawing. Also, it will again be understood that the
distal portion 210 shown in FIG. 21 can be the distal portion of
the deployment system 200 shown more completely in FIG. 4. This is
simply a matter of configuring ejection control elements 260 and
270 in FIG. 4 appropriately to proximally retract release wires 292
when it is desired to eject magnetic devices 100.
[0118] FIG. 22 shows another alternative embodiment of distal
portion 210 in which at least portions of the side wall of each
recess 212 are inclined away from one another in the direction from
the bottom of the recess toward the open end of the recess. The
resilient prongs 110 of the magnetic device 100 in each recess
engage these anticlinal recess wall surfaces in such a way that the
spring force of the prongs tends to eject the magnetic device from
the recess. Initially, however, each magnetic device 100 is held in
its recess 212 by an associated release wire 292a or 292b, which
releasably engages the magnetic device. This releasable engagement
can be mechanical (e.g., release wire extending into or through a
recess or hole in magnetic device), magnetic (e.g., magnetic device
magnetically attracted to ferromagnetic release wire), or the like.
When it is desired to eject a magnetic device 100 from its recess,
the release wire 292 for that magnetic device is pulled proximally
(as shown on the right in FIG. 22). The spring force of prongs 110
acting on the anticlinal recess wall surfaces ejects the associated
magnetic device from the recess and implants the magnetic device in
the esophageal wall tissue. Once again, what is shown in FIG. 22
can be the distal portion 210 of a more complete delivery system
like that shown in FIG. 4. Also, the lumens for use in inflating
balloon structures 216 are omitted from FIG. 22 to simplify the
drawing.
[0119] FIG. 23 shows another alternative embodiment of distal
portion 210 of a deployment system which produces distention of the
esophagus prior to ejection of magnetic devices 100 in another way.
In this embodiment the left (211a) and right (211b) parts of the
main body of distal portion 210 are separated from one another by
an inflatable (e.g., balloon or balloon-like) structure 216. For
example, left and right parts 211a and 211b may be secured to
respective opposite sides of inflatable structure 216. Distal
portion 210 is initially positioned in the patient with structure
216 deflated and with parts 211a and 211b relatively close to one
another. When it is time to eject magnetic devices 100 from
recesses 212, structure 216 is inflated as shown in FIG. 23 by
supplying pressurized fluid to structure 216 via inflation lumen
218. This distends the patient's esophagus, pressing both sides of
distal portion 210 more firmly against the esophagus and stretching
the esophageal tissue over the entrances to recesses 212a and 212b.
Magnetic devices 100 are then ejected and implanted by proximally
retracting wedge pull wires 282 in order to raise deployment wedges
280 (similar to what is shown in FIGS. 11-19 and described above).
In this embodiment both of magnetic devices 100 can be driven at
the same time, or they can be driven one after the other as in the
earlier-described embodiments. If the distal portion 210 of FIG. 23
is used in a system like that shown in FIG. 4, only one element
like 240/250 is needed because one inflatable structure 216 does
all the final lateral positioning of the distal components.
Similarly, if both of magnetic devices 100 are driven at the same
time, it may be possible to include only one element like 260/270
in a system of the FIG. 4 type because both of deployment wedges
280 are going to be operated at the same time by what can be a
common control.
[0120] Although FIG. 23 shows wedge deployment of magnetic devices
100, any of the other types of magnetic device deployment taught
herein can instead be used in a system that is otherwise like what
is shown in FIG. 23 if desired. For example, pressured fluid
deployment as shown in any of FIG. 3, 5, or 20 can be used. Or
spring-powered deployment like that shown in FIG. 21 or 22 can be
used.
[0121] Still another illustrative embodiment of distal portion 210
is shown in FIGS. 24 and 25. This embodiment is somewhat like the
FIG. 23 embodiment, except that in this case the left (211a) and
right (211b) parts of distal portion 210 are separated (when
desired) by pulling shim structure 217 proximally back between them
as shown in FIG. 25. In other words, the structure is first
positioned in the patient in a condition like that shown in FIG. 24
with shim structure 217 distal of separable parts 211a and 211b.
Then to finally prepare for deployment of magnetic devices 100,
shim structure 217 is pulled proximally back between those parts as
shown in FIG. 25 by pulling shim pull wire 219 proximally. This
distends the tissue in the same way that inflation of structure 216
in FIG. 23 distends the tissue. With the tissue thus distended,
magnetic devices 100 can be deployed in the same way that has been
described above in connection with FIG. 23. Shim structure 217 can
be a basically cylindrical body with one end portion tapered and
the other end portion rounded. Variations and modifications
suitable for embodiments like that shown in FIG. 23 are also
suitable for the FIGS. 24 and 25 embodiments. Similarly,
modifications of what is shown in FIG. 4 for use with FIG. 23 are
also possible for FIGS. 24 and 25 embodiments.
[0122] In some embodiments of the invention it may be desirable to
first mark the wall of the esophagus with marks that facilitate
later observation (e.g., visualization) of the esophagus, and
especially the points on the esophagus to which magnetic devices
100 are to be applied. FIG. 26 shows the distal portion of an
illustrative embodiment of marking apparatus 300 in accordance with
the invention. This apparatus is designed for delivery of its
distal portion into a patient's esophagus via the patient's
mouth.
[0123] Marking apparatus 300 includes main delivery catheter 310.
One or more secondary catheter-like tubes 320a and 320b are
selectively extendable from the side wall of main delivery catheter
310. Typically, main delivery catheter 310 is introduced into the
patient with secondary tubes 320 retracted into the main catheter.
When main catheter 310 is properly positioned in the patient,
secondary tubes 320 are extended from the main catheter to somewhat
distend and press against the side wall of the esophagus at the
locations that are to be marked. Then a marking element 330a or
330b is extended from each secondary tube 320. For example, each
marking element 330 may include a needle for injecting visible
and/or radiopaque dye, an electrically conductive wire for the
transmission of radio frequency energy, a structure for performing
argon plasma cautery, or a lumen for transmission of vacuum (to
visibly redden the tissue surface by drawing extra blood to
it).
[0124] FIG. 27 shows the distal-most portion of esophagus marking
apparatus 300 positioned at the level of the lower esophageal
sphincter 40. Esophagus marking elements 330a and 330b have been
extended substantially radially and marks 340a and 340b have been
placed on the surface or internal to the esophageal wall.
[0125] After marks 340a and 340b have been applied, apparatus 300
can be removed from the patient by pulling it out of the patient's
mouth. Marks 340a and 340b can thereafter be used to help guide
proper placement of magnetic devices in the patient. Marks 340 can
be observed visibly, radiologically, or in any other way that is
suitable in view of the type of marks and the other apparatus
employed. Any of the previously shown and described magnetic device
deployment apparatuses and methods can be used with marking methods
and apparatus such as have just been described. The same is true
for any of the other magnetic device implanting methods and
apparatuses that will be described later in this specification.
[0126] Marking apparatus 300 typically includes proximal components
(not shown) that remain outside the patient at all times and that
are used for controlling the depicted distal portions of the
apparatus. Although these proximal components are not shown, they
may be generally in the nature of the proximal componentry shown in
FIG. 4, i.e., a control element for axially positioning main
catheter 310 in the patient, one or more control elements for
shifting secondary tubes 320 axially relative to main catheter 310,
one or more control elements for shifting marking structures 330
axially relative to tubes 320, and one or more control elements for
controlling marking structures 330 to actually produce marks
340.
[0127] FIG. 28 shows the distal portion 410 of another illustrative
embodiment of apparatus 400 for implanting a magnetic device 100 in
the esophagus of a patient. Apparatus 400 includes elongated,
hollow, delivery catheter 420, which is insertable into the
patient's esophagus via the patient's mouth. Like other delivery
catheter structures described earlier in this specification,
delivery catheter 420 is sufficiently flexible to pass through the
mouth and down the esophagus, but it also has sufficient column
strength that it can be pushed down the esophagus without folding
back on itself undesirably. The extreme distal end portion of
catheter 420 includes magnetic device holder 422 (e.g., a short,
hollow tube for holding magnetic device 100 with the resilient
prongs 110 of that device deflected). Inside of catheter 420 is a
structure 430 for ejecting magnetic device 100 from holder 422 when
it is desired to implant the magnetic device in the tissue of the
patient. The relatively distal portion of one or more of structures
420 and 430 may include some "steerability," i.e., capability of
being controllably deflected laterally or transversely relative to
the main longitudinal axes of the apparatus and the patient's
esophagus. Such steerability allows the distal end of structure
420/422 to be laterally deflected toward the side wall of the
esophagus when the apparatus is properly positioned in the patient
and it is desired to drive magnetic device 100 into the esophageal
wall tissue. This lateral deflection of the apparatus may also be
used to distend the esophagus and thereby help to press the free
end of structure 422 more firmly against the esophageal wall.
[0128] FIG. 29 shows apparatus 400 inserted in a patient's
esophagus and with distal portion 410 steered laterally toward
previously applied mark 340b. Note that (as suggested above) an
effect of this lateral steering is to brace an intermediate portion
of structure 420 against the wall of esophagus 10 opposite mark
340b so that the free end of structure 420 will be pressed against
the tissue at mark 340b. When the apparatus is in a condition like
that shown in FIG. 29, magnetic device ejection structure 430 can
be operated to drive magnetic device 100 from structure 420/422
into the patient's esophageal wall tissue at mark 340b.
[0129] Ejection structure 430 can be (or represent) any of a wide
range of components for driving magnetic device 100 from the
surrounding structure 422. For example, ejection structure 430 can
be a mechanical pusher. Or structure 430 can be (or represent)
structure for achieving ejection of magnetic device 100 by means of
pressurized fluid. As still another example, ejection can be by any
of the above-described releasable spring methods or apparatus, and
structure 430 can represent the required spring and/or spring
release components.
[0130] After magnetic device 100 has been implanted at mark 340b,
apparatus 400 can be withdrawn from the patient via the patient's
mouth. Any lateral steering of apparatus 400 can be relaxed during
withdrawal to facilitate such withdrawal. Reloaded apparatus 400 or
a second similar apparatus can then be inserted into the patient to
install a second magnetic device 100 at mark 340a.
[0131] Again, although not shown in the FIGS., apparatus 400
typically includes various control components that remain outside
the patient at all times. These control components can generally be
like appropriate ones of the control components shown in FIG. 4.
The control components that will generally be needed will be
components for controlling (1) longitudinal placement of distal
portion 410 in the patient's esophagus, (2) lateral steering of
distal portion 410, and (3) ejection of magnetic device 100.
[0132] Some illustrative alternative embodiments for retention
structures 110 for securing a magnetic device 100 to a patient's
tissue are shown in FIGS. 30-32. In FIG. 30 retention structure 110
is configured as or like a helical spring extending from the main
body of magnetic device 100. The free end of spring 110 is
preferably sharpened to facilitate tissue penetration. In FIG. 31
retention structure 110 is a barbed spike extending substantially
perpendicularly from the main body of magnetic device 100. The
barbs 115 on spike 110 resist removal of the device from tissue
into which spike 110 has been driven. In FIG. 32 retention
structure 110 is a pair of wire-like prongs that first extend away
from one another where they leave the main body of magnetic device
100. Toward their free ends, prongs 110 curve back toward one
another. Again, the free ends of prongs 110 are preferably
sharpened to facilitate tissue penetration.
[0133] In FIG. 33 the shape of the main body of magnetic device 100
is different from the round or disk shape that has generally been
shown in earlier FIGS. FIG. 33 shows the main body of device 100 as
elongated, but any of many other shapes (e.g., square, rectangular,
etc.) can also be used if desired. The thickness of the main body
of a magnetic device 100 can also vary or be uniform.
[0134] FIG. 34 shows a distal portion of illustrative apparatus in
accordance with the invention for removing magnetic devices that
have been implanted in a patient, if desired. Apparatus 500 is
insertable into the patient's esophagus via the patient's mouth
when it is desired to use the apparatus. Apparatus 500 includes a
delivery catheter 510, within which are longitudinally or axially
reciprocable stylet structure 520 and snare structure 530. Snare
structure 530 includes a hollow, tubular snare sheath (also
referred to by reference number 530) and snare 532 longitudinally
or axially reciprocable within snare sheath 530. The distal end of
snare 532 is a loop of wire or wire-like material that is
resiliently biased to spring open as shown in FIG. 34 when extended
from the distal end of snare sheath 530. However, this open loop
can be closed down by pulling it into (or partly into) the distal
end of snare sheath 530.
[0135] FIG. 35 shows that apparatus 500 can be used with or can be
part of endoscope apparatus 600 (which can otherwise be
conventional). FIG. 35 also shows the start of use of the apparatus
to remove one or both of magnetic devices 100a and 100b from a
patient's esophagus 10. In FIG. 35 apparatus 500/600 has been
inserted into esophagus 10 via the patient's mouth and has been
pushed down to just above the lower esophageal sphincter 40. Stylet
520 has then been extended so that its enlarged distal end 522
extends below magnetic devices 100a and 100b.
[0136] The next step in use of the apparatus is shown in FIG. 36,
in which the distal end of snare structure 530 has also been
extended below magnetic devices 100, passing those devices on the
side opposite the side on which stylet 520 previously passed those
devices.
[0137] In FIG. 37 snare loop 532 is extended from the distal end of
snare sheath 530 so that loop 532 can open. Stylet 520 and snare
structure 530 are then manipulated until the enlarged distal end
522 of stylet 520 passes through snare loop 532.
[0138] In FIG. 38 snare loop 532 is pulled back into snare sheath
530 to again reduce the size of snare loop 532 and thereby capture
the distal end 522 of stylet 520. Stylet 520 and snare structure
530 now form a secure loop that extends around at least one of
magnetic devices 100.
[0139] FIG. 39 shows proximal retraction of all of structure 600,
510, etc. This removes at least one of the magnetic devices (e.g.
100b) from the patient's tissue. Removal of apparatus 600, 510,
etc. from the patient's mouth takes at least this one magnetic
device 100 out of the patient. With at most only one device (e.g.,
100a) remaining in the patient, there is no longer any magnetic
closing of sphincter 40, so the treatment of that sphincter in
accordance with this invention has effectively been reversed. If
only one of magnetic devices 100 came out with the first use of
apparatus 500/600, that apparatus can be used again to retrieve the
other magnetic device if desired.
[0140] FIG. 40 shows another illustrative embodiment of apparatus
for removing magnetic device(s) 100 from a patient's esophagus
after those devices have been implanted in the esophagus. This
embodiment may again make use of endoscope 600, which can
facilitate delivering magnetic device removal apparatus 650 to the
proper location in the patient. For example, after magnetic devices
100 have been visualized via endoscope 600, then removal apparatus
650 may be inserted through a tool lumen in the endoscope and
extended beyond the distal end of the endoscope as shown in FIG.
40. Removal apparatus 650 includes a distal portion 652 which is
(or which, via electromagnetism, can be selectively made to be) a
magnet strong enough to attract magnetic devices 100 and pull them
from the wall of the patient's esophagus as shown in FIG. 40. When
magnetic devices 100 have thus been pulled out of the tissue, all
of apparatus 600, 650, and 652 can be pulled out of the patient via
the patient's mouth, thereby completely removing magnetic devices
100 from the patient.
[0141] FIG. 41 shows an illustrative embodiment of apparatus 700 in
accordance with the invention for changing the magnetism of one or
more of magnetic devices 100 after they have been implanted in a
patient. The change in magnetism referred to in the preceding
sentence can be (1) magnetizing a previously unmagnetized device
100, (2) demagnetizing a previously magnetized device 100, or (3)
increasing or decreasing the magnetic strength of a previously
magnetized device 100. Apparatus 700 includes a catheter-like
central or medial portion 710 for use in delivering a distal end
portion 720 of the apparatus to the location of previously
implanted magnetic devices 100. The distal end portion 720 of
apparatus 700 includes an electromagnetic structure to which
electrical current can be supplied via leads 730a and 730b. When
the electromagnetic structure of distal portion 720 is electrically
energized via leads 730, distal portion 720 produces a magnetic
field suitable for producing the desired change in the magnetism of
one or more of devices 100. A suitable permanent magnetic structure
may be used for distal portion 720 instead of an electromagnet if
desired.
[0142] As an alternative to introducing apparatus like 700 into the
patient, similar results may be obtained by placing a suitable
magnetic field source near the patient (but outside the patient's
body) to change the magnetism of one or more of magnetic devices
100.
[0143] Various objectives may be achieved by changing the magnetism
of devices 100 after they have been implanted. For example, if the
patient's GERD has not improved sufficiently, the strength of
magnetic devices 100 may be increased to see if that will help.
Alternatively, if the closure of sphincter 40 is now too strong,
the strength of magnetic devices 100 may be reduced. As still
another example, demagnetizing magnetic devices 100 may be used as
an alternative to physically removing them from the patient to
reverse or terminate treatment in accordance with the
invention.
[0144] FIGS. 42-49 show another illustrative construction of
magnetic devices 100 in accordance with the invention, and
illustrative apparatus for implanting such devices, also in
accordance with the invention. As shown in FIG. 42, this
illustrative embodiment of a magnetic device 100 includes a
disk-shaped permanent magnet 105 embedded in an external structure
shell 107. As in other embodiments, magnet 105 can be made of any
material capable of producing a magnetic field. Again (as for other
embodiments), the preferred materials are rare earth magnets
because of their superior field strength. Especially preferred
materials include Alnico (aluminum/nickel/cobalt), SmCo
(samarium/cobalt), and NdFeB (neodymium/iron/boron). Also as for
other embodiments, the magnetic force exerted will depend on
various factors, including material, length, and width of the
magnet. The required magnet strength depends on the forces needed
to improve the closing function of a lower esophageal sphincter,
while allowing fluids and solids to enter the stomach. Also as for
other embodiments, body 105 in the FIGS. being discussed can be
passively magnetic (rather than actively magnetic) in one or more
of devices 100, as long as any such passively magnetic device(s) is
(are) used so as to cooperate with one or more other actively
magnetic devices 100.
[0145] Suitable material for external shell 107 in the FIGS. being
discussed (as for other embodiments) are preferably non-porous,
biocompatible, biostable, corrosion resistant, and of sufficient
structural integrity to absorb in-vivo loads. Such materials
include, but are not limited to, known implantable metals such as
stainless steel or titanium, high-density polymers such as parylene
or ultra-high molecular weight polyethylene, or materials made from
non-metallic minerals such as ceramic or glass.
[0146] An aperture 110 extends through shell 107 across a diameter
of device 100 to aid in securing the assembly to the esophageal
wall as will be described in subsequent paragraphs.
[0147] FIG. 43 shows an illustrative, wire-like stylet 800 for use
in implanting magnetic devices 100 of the type shown in FIG. 42 in
a patient. Although stylet 800 could be constructed differently, in
the particular embodiment shown in FIG. 43 stylet 800 includes a
non-ferrous longitudinal member 810 with ferrous segments 820
spaced along the length of the longitudinal member. Longitudinal
member 810 is a structural component with a sharpened distal end
812 designed to penetrate the esophageal wall and traverse through
the lumen 110 in each magnetic device 100 of the type shown in FIG.
42 in order to stitch the assembly in place in the patient. Ferrous
segments 820 are designed to magnetically attract retention stylet
800 to each individual magnetic device 100. The magnetic force
established between the magnetic device(s) 100 and ferrous
segment(s) 820 helps to hold stylet 800 in place. Stylet 800 could
additionally or alternatively be provided with a mechanical
mechanism to lock the magnetic device(s) 100 in place.
[0148] FIG. 44 shows several magnetic devices 100 of the type shown
in FIG. 42 secured to one side of a patient's esophagus 10 by a
stylet 800. Note that a ferrous segment 820 is positioned adjacent
each magnetic device 100 in FIG. 44.
[0149] FIG. 45 shows the distal portion of an illustrative
embodiment of a delivery system 900 for implanting magnetic devices
100 like those shown in FIGS. 42 and 44 (using stylets 800 as shown
in FIGS. 43 and 44) in accordance with the invention. Apparatus 900
may be designed to removably accept an endoscope 910, shown in FIG.
45 traversing the length of the remainder of apparatus 900.
Multiple magnetic devices 100 (100a on the left and 100b on the
right) are positioned on each side of a longitudinal delivery
structure 920 at respective peaks in serpentine exterior surfaces
922 of a relatively distal portion of structure 920. Magnetic
devices 100 are held in place at these locations in structure 920
by their magnetic attraction to ferrous or magnetic tube 930 that
is removably disposed inside structure 920 coaxially around
endoscope 910. A substantially radial orifice 924 extends through
each valley in each serpentine surface 922 and communicates with a
vacuum lumen 926 that extends along the length of the apparatus
inside structure 920. Magnet retention stylets 800 (800a on the
left and 800b on the right) are contained in stylet advancement
lumens 928 that are proximal of but axially aligned with each set
of magnetic devices 100. Stylet advancement rods 940 (940a on the
left and 940b on the right) are positioned proximally of retention
stylets 800 for use in driving stylets 800 in the distal direction
at the appropriate time.
[0150] FIG. 46 shows the distal portion of delivery system 900
positioned in a patient's esophagus 10 with magnetic devices 100 in
the vicinity of lower esophageal sphincter 40. This condition has
been achieved by inserting the apparatus via the patient's mouth.
As in FIG. 4 and other embodiments, control portions of apparatus
900 remain outside the patient for operation by the user (a
physician or the like) of the apparatus. The outside diameter of
delivery apparatus 900 is designed to be large enough relative to
the inside diameter of the esophagus to create a relatively
air-tight seal between the apparatus and the surrounding
tissue.
[0151] FIG. 47 shows the next step in use of the apparatus being
discussed. In this step reduced gas pressure (i.e., sub-atmospheric
or "vacuum" pressure) is applied to vacuum lumen 926 from a source
of reduced gas pressure outside the patient. This reduced gas
pressure is communicated to the wall of the patient's esophagus 10
via radial orifices 924, which causes the wall of the esophagus to
closely conform (i.e., follow) the serpentine surfaces 922 of the
lower portion of delivery structure 920. This places tissue of the
esophagus wall directly above and below each of magnetic devices
100 and aligned with a downward projection of each of magnet
retention stylets 800.
[0152] The next step (shown in FIG. 48) is to advance stylet
advancement rods 940a and 940b in the distal direction. This drives
magnet retention stylets 800a and 800b through the esophageal
tissue and through the apertures 110 (FIG. 42) in magnetic devices
100a and 100b. Stylets 800 thus now secure magnetic devices 100 to
the wall of the esophagus on opposite sides of the esophageal
lumen.
[0153] The next step (not separately depicted) is to release the
vacuum applied to lumen 926 and orifices 924, and to proximally
withdraw (or at least shift) ferrous or magnetic tube 930. This
movement of tube 930 removes it from the vicinity of magnetic
devices 100, thereby releasing devices 100 from deployment
apparatus 900. Positive (above-atmospheric) gas or liquid pressure
may then be applied to passageways 926 and 922 to help separate
elements 100 and 800 from delivery apparatus 900. Stylet
advancement rods 940 may also be proximally retracted to ensure
that they do not pin any tissue to deployment apparatus 900.
Deployment apparatus 900 may then be pulled proximally out of the
patient's mouth, leaving behind elements 100 and 800 in the
condition shown in FIG. 49. In particular, FIG. 49 shows that
magnetic attraction between magnetic elements 100a and 100b on
respective opposite sides of the esophageal lumen helps to close
that lumen in the vicinity of lower esophageal sphincter 40. Of
course, the esophageal lumen opens, at least in part, when liquids
or solids are swallowed by the patient or when pressure in the
patient's stomach 30 becomes significantly higher than normal.
[0154] Although FIGS. 44-49 show implanting two lines of three
magnetic devices each, it will be understood that this approach can
be adapted to implanting any number of magnetic devices in each
line (e.g., one device, two devices, three devices (as shown), or
more than three devices per line), and to implanting any number of
lines of such devices (e.g., one line, two lines (as shown), three
lines, four lines, or more than four lines).
[0155] FIGS. 50-53 show a generalized embodiment having two lines
of magnetic devices 100a and 100b on respective opposite sides of
esophagus 10. (In FIGS. 50 and 51, esophagus 10 is shown open; in
related FIGS. 52 and 53, esophagus 10 is shown closed.) In other
words, these two lines of magnetic devices 100a and 100b are
positioned diametrically opposite one another (approximately
180.degree. apart in the direction circumferentially or annularly
around esophagus 10). FIG. 51 shows that magnetic devices 100a (on
one side of esophagus 10) have magnetic polarity opposite the
magnetic polarity of magnetic devices 100b (on the other side of
esophagus 10). (The placement of "negative polarity" on the left
and "positive polarity" on the right is entirely arbitrary and can
be reversed if desired.) Because of their opposite magnetic
polarities, magnetic devices 100a and 100b are mutually attracted
to one another, thereby helping to hold the esophagus normally
closed as shown in FIGS. 52 and 53.
[0156] FIGS. 54-57 show another generalized embodiment having two
sets of three substantially parallel lines of magnetic devices
100a1-3 and 100b1-3 on respective opposite sides of esophagus 10.
(In FIGS. 54 and 55, esophagus 10 is shown open; in related FIGS.
56 and 57, esophagus 10 is shown closed.) The three lines of
magnetic devices 100a1-3 on one side of the esophagus have one
magnetic polarity (identified as "negative polarity" in FIG. 55),
while the three lines of devices 100b1-3 on the opposite side of
the esophagus have the opposite magnetic polarity (identified as
"positive polarity" in FIG. 55). (Again the choice of which side is
positive and which is negative is arbitrary and can be reversed if
desired.) Because of their opposite magnetic polarities, magnetic
devices 100a1-3 and 100b1-3 are mutually attracted to one another,
thereby helping to hold the esophagus normally closed as shown in
FIGS. 56 and 57. In particular, magnetic devices 100a1 and 100b1
are mutually attracted to one another, magnetic devices 100a2 and
100b2 are mutually attracted to one another, and magnetic devices
100a3 and 100b3 are mutually attracted to one another. Because some
of devices 100a are now spaced from one another circumferentially,
and some of devices 100b are similarly spaced from one another
circumferentially, the esophagus-closing forces exerted by the
magnetic attraction of these devices is similarly distributed
circumferentially. In other words, a circumferentially wider
portion of one side of the esophagus is now attracted to a
circumferentially wider portion of the opposite side of the
esophagus (as compared, for example, to the embodiment shown in
FIGS. 50-53). This greater circumferential distribution of the
esophagus-closing force produced by magnetic devices 100 may be
preferable in some instances.
[0157] FIG. 58 illustrates an embodiment in which the strength of
magnetic devices 100 is different at different locations in an
implanted array of such devices. In the particular embodiment shown
in FIG. 58 the strength of magnetic devices 100 (implanted in two
parallel lines axially along respective opposite sides of esophagus
10) increases in the distal direction along the esophagus. (FIG. 58
shows the esophagus open and as though transparent to render
visible the magnetic devices 100 implanted inside the esophagus.)
Thus the magnetic attraction between devices 100a1 and 100b1 is
weakest, the attraction between devices 100a2 and 100b2 is somewhat
stronger, and so on until the strongest magnetic attraction is
provided between devices 100a5 and 100b5. As a result of this
progression of magnetic force strength, FIG. 58 indicates
diagrammatically that the force required to separate the various
pairs of magnets and open the associated portions of the esophagus
increases from top to bottom of the array. Thus "lower separating
force" is required to open the portion of the esophagus near the
top of the array of magnetic devices 100, and "higher separating
force" is required to open the portion of the esophagus near the
bottom of the array. Magnets with less attractive strength at the
upper end of the array may increase the ability of the supported
esophagus to open during swallowing of fluids or solids, while
stronger magnets at the lower end of the array may better resist
stomach acid from exiting the stomach via the lower esophageal
sphincter.
[0158] FIG. 59 shows another example of a possible construction of
a representative magnetic device 100. This embodiment can be
generally similar to the embodiment shown in FIG. 31. FIG. 59 shows
a magnetic device 100 having a magnetic body 105 (which can be
either actively or passively magnetic) embedded in a shell 107.
Retention structure 110 extends from one side of shell 107.
Retention structure 110 has a sharply pointed free end or tip
remote from magnetic body 105. This sharply pointed tip helps
retention structure 110 penetrate tissue during implantation. Back
from the pointed tip along retention structure 110 the retention
structure includes a plurality of radially (or transversely)
outwardly extending barbs 115 that are shaped and oriented to enter
tissue relatively easily, but to resist subsequent withdrawal from
the tissue. Thus each barb 115 has one side that is substantially
parallel to the adjacent inclined side of the free end tip of
retention structure 110 and a second side that is more steeply
transverse to the longitudinal axis of retention structure 110. The
more gradually inclined side of each barb 115 enters tissue
relatively easily. But the more steeply sloped "back" side of each
barb does not encourage tissue to slip back over the extreme outer
tip of that barb in the event that withdrawal force is applied to
the magnetic device. Accordingly, barbs 115 help to hold magnetic
device 100 securely to tissue into which retention structure 110
has been driven.
[0159] FIG. 60 shows another illustrative embodiment of apparatus
1000 for deploying magnetic devices 100 in accordance with the
invention. In FIG. 60 apparatus 1000 is shown deploying magnetic
devices 100 of the type shown in FIG. 59. However, this is only
illustrative, and apparatus like 1000 can be used with differently
configured magnetic devices 100 if desired.
[0160] In the embodiment shown in FIG. 60, magnetic devices 100 are
releasably attached to the outside of an inflatable balloon 1010
that is part of apparatus 1000. Balloon 1010 is initially deflated,
and it may be introduced into the patient's esophagus (not shown)
inside a delivery catheter (also not shown). Introduction may be
via the patient's mouth. When the magnetic devices 100 on balloon
are at the desired location in the esophagus, the delivery catheter
is retracted proximally to expose balloon 1010 and devices 100.
Balloon 1010 is then inflated (as shown in FIG. 60) to drive
magnetic devices 100 into the esophageal tissue on opposite sides
of the esophageal lumen. Balloon 1010 is then deflated, and
apparatus 1000 is withdrawn from the patient via the patient's
mouth.
[0161] FIGS. 61-64 show a generalized illustrative embodiment in
which magnetic devices 100 having the same (rather than opposite)
polarity are employed. (FIGS. 61 and 62 show esophagus 10 open;
FIGS. 63 and 64 show esophagus 10 closed.) "Having the same
polarity" means that the magnetic poles of magnetic devices 100
that have the strongest magnetic interaction with one another are
oriented so that those devices magnetically repel one another. In
other words, the polarities of the poles of two magnetic devices
100 that face one another are the same so that those devices will
repel one another (rather than attract one another as in previously
depicted embodiments). For example, in FIGS. 61-64 all of devices
100 may have their "positive" or "north" pole facing in toward the
center of the lumen of esophagus 10. Alternatively, all of devices
100 may have their "negative" or "south" pole facing in toward the
center of the lumen of esophagus 10. The result of either of these
magnetic orientations of devices 100 is that each of magnetic
devices 100a repels the diametrically opposite magnetic device
100b. This causes the magnetic devices on opposite sides of
esophagus 10 to push those portions of the esophagus apart as shown
in FIGS. 63 and 64. Pushing those parts of the perimeter of the
esophagus apart pulls the intervening portions of the esophagus
perimeter together as is also seen in FIGS. 63 and 64 (especially
FIG. 64). This helps to hold the esophagus normally closed, as is
desired to combat GERD.
[0162] FIG. 65 shows another illustrative embodiment in which
magnetic devices 100 are held in position on the inner surface of
the wall of esophagus 10 by other retention magnets 110 that are
embedded farther into the tissue of the esophageal wall. (FIG. 65
shows esophagus 10 open.) In other words, each magnetic device 100
is magnetically attracted to a retention magnet 110 in the wall of
the esophagus. This magnetically holds each magnetic device 100 in
the desired position on the inner surface of the esophageal wall.
Illustrative apparatus that can be used to implant retention
magnets 110 is shown in later FIGS. and described below. Once
retention magnets 110 are implanted, magnetic devices 100 can be
implanted adjacent to them (e.g., by apparatus of the general type
shown in FIG. 60; see alternatively FIGS. 71-73).
[0163] FIG. 66 shows yet another illustrative embodiment in which
magnetic devices 100 are embedded in the tissue of the esophagus,
rather than being largely on the surface of that tissue. (Once
again, FIG. 66 shows esophagus 10 open.) This embodiment is
somewhat like the embodiment shown in FIG. 65, except that now the
magnets embedded in the tissue are the primary magnetic devices
100, rather than additional retention magnets 110 for the primary
magnets. Illustrative apparatus that can be used to implant
magnetic devices 100 as shown in FIG. 66 is shown in later FIGS.
and described below.
[0164] FIG. 67 shows yet another illustrative embodiment of means
for securing magnetic devices 100 to the wall of esophagus 10.
(Esophagus 10 is again shown open in FIG. 67.) In this embodiment
each magnetic device 100 is held to the esophageal wall by a pin
110 that passes through the magnetic device into the tissue wall.
Each pin 110 has one or more barbs 110a on the portion that
penetrates tissue. Barbs 110a resist being pulled back out of the
tissue and thereby help to secure the associated magnetic device
100 to the tissue. An enlarged head 110b on each of pins 110
prevents the associated magnetic device 100 from coming off the
pin. Illustrative apparatus that can be used for implanting
magnetic devices 100 of the type shown in FIG. 67 is shown in FIG.
60 and described above.
[0165] FIG. 68 shows an illustrative embodiment of a variation on
what is shown in FIGS. 42-49 and described above. (FIG. 68 again
shows esophagus 10 open.) In FIG. 68 each magnetic device 100 is
held in place in esophagus 10 by an associated retention stylet
800. In this embodiment significantly more of each stylet 800 is in
the tissue above the associated magnetic device 100 than is in the
tissue below that device. When the patient swallows something, the
progressive opening of the esophagus proceeding in the distal
direction causes the relatively long upper portions of stylets 800
to first pivot apart and thereby begin separation of magnetic
devices 100a and 100b from one another. This makes it relatively
easy for swallowing to separate the magnets. Any attempted reflux
in the opposite direction, however, does not operate relatively
long lever arms of stylets 800 as has just been described for
swallowing. The structure therefore resists separation of magnetic
devices 100a and 100b more strongly for reflux than for swallowing,
which may be beneficial to combat GERD without increasing
resistance to swallowing to the same degree.
[0166] FIG. 69 shows illustrative apparatus for embedding magnetic
devices 100 in the tissue of the wall of a patient's esophagus 10.
Thus apparatus of this kind can be used to produce the implants
shown in FIG. 66 or to implant retention magnets 110 as shown in
FIG. 65. In the embodiment shown in FIG. 69 a pair (or more) of
magnetic devices 100 are delivered intra-murally into esophagus 10.
A cannula catheter 1100 is inserted trans-orally and advanced to
the site of the lower esophageal sphincter 40. (FIG. 69 shows two
cannula catheters 1100, but it may be preferable to use two such
catheters one after the other (one on each side of the esophagus)
or to use one catheter for two successive installations (one on
each side of the esophagus).) The cannula 1100 then pierces and
enters the wall of the esophagus. After the desired degree of
penetration, a magnetic device 100 is forced out of the distal end
of the cannula to embed the device in the tissue. The cannula is
then withdrawn from the tissue, leaving behind the implanted
magnetic device 100 (and possibly a cannula exit 1110, which soon
heals). Ultimately the cannula is completely withdrawn from the
patient. Magnets 100a and 100b (installed on respective opposite
sides of the esophagus as has just been described) are of opposite
magnetic polarity so that they magnetically attract one another
(see FIG. 70, which shows the end result of the implantation shown
in-progress in FIG. 69). The two magnets add bulk and tone (or
pressure) to the LES. In the absence of devices 100, transient
relaxation of the LES may allow that sphincter to open at low
pressure, permitting reflux and the condition known as GERD. To
overcome this low pressure relaxation, the magnetic force of
magnets 100 is added to the closing tone pressure of the LES. The
amount of this magnetic force can be tailored to an individual's
clinical requirement. Because the LES is mostly closed, the mutual
attraction of magnetic devices 100 will help to prevent their
migration in the tissue from the locations in which they are first
implanted. It will be apparent from what has been said that this
invention provides the advantages of adding a bulking agent to the
esophagus which does not migrate and which increases LES tone
directly related to the magnetic force applied.
[0167] FIGS. 71-73 show an embodiment like that shown in FIG. 65,
but with some additional details. In FIG. 71 each of magnetic
devices 100a and 100b is shown held on the surface of the
esophageal wall on a respective side of the esophageal lumen at or
near LES 40 by an associated retention magnet 110 embedded in the
tissue of the esophageal wall. On each side of the esophagus,
magnets 110 and 100 are inserted either simultaneously or
intra-mural magnet 110 first. The two magnets 100 and 110 in each
such pair attract one another with at least some esophageal tissue
in between. The geometry of the magnets may be selected to allow
for additional mechanical securement between the magnets and also
to conform to natural anatomical geometry (e.g., curved to match
the curve of the esophageal wall). The matching and cooperating
magnets help to prevent migration of either magnet. The intra-mural
magnet 110 secures the associated intraluminal magnet 100.
Typically the magnet pair on one side of the esophagus is implanted
first, and then the magnet pair on the other side is implanted.
Typical spacing between the magnet pairs is approximately
180.degree. in the circumferential direction around the esophageal
lumen. The implanted first and second pairs of magnets attract one
another, providing a magnetic force to add tone pressure to the LES
40 or to modify the closing geometry to reduce or eliminate
reflux.
[0168] FIGS. 72 and 73 show illustrative apparatus 1200 for
implanting pairs of magnets 100 and 110 as shown in FIG. 71. A
cannula catheter 1200 can be inserted into the patient's esophagus
10 via the patient's mouth. When the distal end of the catheter
1200 reaches the proper location (adjacent LES 40), one branch 1210
of the catheter is made to penetrate the tissue of the esophageal
wall as shown in FIG. 72. Then a retention magnet 110 is pushed (by
magnet pusher 1212) from the distal end of branch 1210 to embed
that magnet in the esophageal tissue. At the same time or soon
thereafter, a magnetic device 100a is pushed (by magnet pusher
1222) from the distal end of a second branch 1220 of the catheter.
Magnetic device 100a is magnetically attracted to embedded
retention magnet 110 and thereby held in place in the lumen of
esophagus 10. Delivery apparatus 1200 can then be withdrawn from
the patient as shown in FIG. 73. That apparatus can then be
reloaded and reused (or another similar apparatus can be used) to
implant two more magnets 100b and 110 in the same way on the
opposite side of the esophageal lumen.
[0169] Any of the delivery systems shown and described herein can
be aided by direct visualization, x-ray visualization, echo
visualization, or the like. For example, echo visualization can be
used to determine the depth at which the retention magnets like 110
in FIGS. 65 and 71-73 or the primary magnets 100 in embodiments
like FIGS. 66, 69, and 70 are delivered into the wall of the
esophagus.
[0170] FIGS. 74 and 75 show another illustrative embodiment of the
distal portion 210 of illustrative deployment system 200. In this
embodiment distal portion 210 includes a distal tip portion 1310,
which is preferably relatively soft (e.g., of silicone or a
polymer) to help make the delivery system atraumatic to tissue. A
wire lumen 1312 is formed through tip portion 1310 so that, if
desired, distal portion 210 can be fed into the patient along a
guidewire 1320 that has been inserted in the patient. Use of
guidewire 1320 and guidewire lumen 1312 may improve "trackability"
of the apparatus into the patient. Once distal portion 210 is at
the desired location in the patient, guidewire 1320 can be
withdrawn from the patient, which is why guidewire 1320 is not
visible in FIG. 75.
[0171] The distal portion 210 shown in FIGS. 74 and 75 includes
only a single balloon structure 216, which preferably extends
annularly all the way around a relatively rigid, largely hollow
core member 1330. Balloon structure 216 can be formed by placing a
tube of balloon material annularly around core member 1330 and then
securing each end of that tube to the core member with a respective
one of annular balloon restraints 1340. Each of restraints 1340 is
a ring that fits sufficiently around the adjacent portion of
balloon 216 and core member 1330 to seal the balloon to the core.
The open proximal end of core member 1330 is annularly sealed to
the distal end of the lumen of catheter 220 (e.g., by being
press-fitted into the distal end of the catheter lumen. Core member
1330 has at least one opening 1332 (two are shown) from its hollow
interior to the interior of balloon 216 between restraints 1340.
Accordingly, balloon structure 216 can be inflated as shown in FIG.
75 by supplying pressurized fluid to the interior of core member
1330 via the lumen of catheter 220.
[0172] Balloon structure 216 carries two pockets 1350a and 1350b
for magnetic devices 100a and 100b. Pockets 1350 are on
diametrically opposite sides of distal portion 210, and they pass
freely through above-mentioned openings 1332 in core member 1330.
When balloon 216 is inflated as shown in FIG. 75, pockets 1350 and
magnetic devices 100 move radially outwardly with the adjacent
portion of the surface of balloon 216 (through which pockets 1350
pass with sealing connections to the balloon). As in other
embodiments, inflation of balloon 216 somewhat distends the
adjacent tissue of the esophagus in which distal portion 210 is
located, thereby helping to stretch the esophageal tissue across
the openings of pockets 1350 and preparing that tissue to receive
magnetic devices 100. Magnetic devices 100 can be releasably held
in pockets 1350, and also selectively released or driven from
pockets 1350, using any of several of the techniques described
earlier. In the particularly preferred embodiment shown in FIGS. 74
and 75, pressurized fluid is used to drive each magnetic device 100
from its pocket 1350 (similar to what is shown, for example, in
FIG. 3 and described earlier in connection with that FIG.). Thus
tubes 214 are provided in catheter 220 and into the interior of
core member 1330 to supply pressurized fluid to each of pockets
1350 behind the magnetic device 100 in that pocket when it is
desired to drive the magnetic device from its pocket. A difference
from FIG. 3 is that in FIGS. 74 and 75 (as has been mentioned)
pockets 1350 travel radially outwardly with the surface of balloon
216 when the balloon is inflated. Accordingly, tubes 214 must have
sufficient flexibility and slack to permit their distal end
portions to also travel radially outwardly with pockets 1350 as
shown in FIG. 75. Tubes 214 also pass through openings 1332 in core
member 1330 when their distal end portions travel radially
outwardly with pockets 1350.
[0173] To conclude this discussion of the FIGS. 74 and 75
embodiment, after balloon 216 has been inflated as shown in FIG.
75, pressurized fluid is supplied to each pocket 1350 via the
associated tube 214 to drive the associated magnetic device 100
from that pocket and into the esophageal tissue that is somewhat
stretched over the exit from the pocket. Balloon structure 216 is
then deflated to restore it to a condition like that shown in FIG.
74, and the apparatus is withdrawn from the patient, leaving only
implanted magnetic devices 100 behind in the patient.
[0174] FIGS. 76-79 show some more examples of how magnetic devices
100 may be implanted in a patient's esophagus 10 in accordance with
the invention. In FIGS. 76 and 77 two pairs or sets of magnetic
devices 100 are implanted at locations that are axially spaced from
one another along esophagus 10. In particular, magnetic devices
100a1 and 100b1 ("set 100-1") are implanted lower in esophagus 10
than magnetic devices 100a2 and 100b2 ("set 100-2"). In addition,
set 100-2 is rotated (in a direction circumferentially of esophagus
10) relative to set 100-1. In particular, set 100-2 is rotated
90.degree. relative to set 100-1. FIGS. 78 and 79 show the addition
of a third set of magnetic devices (100a3 and 100b3 ("set 100-3"))
to what is shown in FIGS. 76 and 77. All three sets in FIGS. 78 and
79 are axially spaced from one another along esophagus 10. In
addition, set 100-2 is rotated relative to set 100-1, but set 100-3
is not rotated relative to set 100-1.
[0175] The use of multiple sets of magnetic devices as shown, for
example, in FIGS. 76-79 allows management of the esophagus 10 if it
does not close symmetrically. For example, if a set of magnets is
deployed with an anterior-posterior orientation, and the esophagus
closes in a left-right lateral direction, the magnets will not come
into contact. By placing two sets--one with an anterior-posterior
orientation and one with a left-right lateral orientation (or
alternatively with any similar 90.degree. angular off-set relative
to one another)--the resulting arrangement of the magnetic devices
will account for any way in which the esophagus may naturally close
and still ensure that at least one set of magnets comes into
contact.
[0176] FIGS. 80 and 81 show yet another illustrative embodiment of
a magnetic device 100 in accordance with the invention. In this
embodiment the actual magnetic material (active or passive) is
contained in a cup-shaped magnet case portion 102. This cup-shaped
portion 102 is closed by disc-shaped case portion 102', which is
secured to cup-shaped portion 102 by such means as a laser weld,
brazing, a press-fit connection, solder, or the like. Wire retainer
structure 104 projects out from the center of the outer major
surface of member 102'. Three elastic wires 110a-c (e.g., of
nitinol) with sharpened free ends extend transversely across wire
retainer structure 104 with angular orientations that are equally
spaced from one another around structure 104. Wires 110 may be held
in structure 104 by several means (e.g., by being press fit into
slots in structure 104 and/or by being pressed into structure 104
by cover or closure 104' (which again may be secured to structure
104 by laser welding, brazing, press fitting, soldering, or the
like). Thus although device 100 as shown in FIGS. 80 and 81 employs
only three wires 110a-c, six retention fingers for securing the
implant result from this construction.
[0177] Although each of the depicted embodiments tends to employ
one type of magnetic device, it will be understood that different
types of magnetic devices (e.g., those from different ones of the
depicted embodiments) can be used together if desired. For example,
an embedded magnet (e.g., as in FIG. 66) on one side of the
esophagus can be used to magnetically interact with a
surface-mounted magnet (e.g., as in FIG. 67) on the other side of
the esophagus. The magnetic devices used together do not all have
to be of the same type or construction.
[0178] Although the invention has been illustratively discussed
primarily in the context of treating GERD, the invention has many
other possible applications, as will be readily apparent to those
skilled in the art from this specification. Examples of its various
possible applications include treatment of a wide variety of body
passages, organs, or cavities in the digestive, respiratory,
circulatory, reproductive, and excretory systems. Treatment in
accordance with the invention may mean increasing strength,
changing shape, restricting flow, decreasing size, changing wall
tension, affecting or effecting tissue movement, or the like. Some
specific examples other than treatment of GERD are mentioned in the
next few sentences. Magnets may be implanted in the stomach to
limit its capacity for food intake by partitioning or restricting
at least a portion of the stomach area from food. This results in
reduced capacity for food intake and subsequent weight reduction.
Conditions such as emphysema may be improved by reducing access of
air intake to diseased sections of lung tissue. Magnets may be used
to collapse or restrict air flow in the bronchial air lumens that
lead to diseased lung sections. This effectively reduces lung
capacity and directs air intake to the healthiest tissue. Other
examples of use of the invention are referred to elsewhere in this
specification.
[0179] It will be understood that the foregoing is only
illustrative of the principles of the invention, and that various
modifications can be made by those skilled in the art without
departing from the scope and spirit of the invention.
* * * * *