Note: Descriptions are shown in the official language in which they were submitted.
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FOOD INTAKE RESTRICTION APPARATUS WITH CONTROLLED WIRELESS
ENERGY SUPPLY
The present invention relates to a food intake restriction
apparatus, comprising a restriction device implantable in an
obese patient, for engaging the stomach or esophagus to form an
upper pouch of the stomach and a restricted stoma opening in the
stomach or esophagus. The term patient includes an animal or a
human being.
Food intake restriction apparatus in the form of a gastric
banding device, in which a band encircles a portion of a
patient's stomach to restrict the food intake of the patient,
have been used in surgery for morbid obesity to form a small
gastric pouch above the band and a restricted stoma opening in
the stomach. Although such a band is applied around the stomach
to obtain an optimal stoma opening during surgery, some prior
gastric banding devices are provided with an adjustment means
enabling a minor post-operation adjustment of the size of the
stoma opening. In all such prior art devices such as disclosed
in U.S. Patent No. 4592339, European Patent No. 0611561 and
International Patent Application WO 94/27504, the adjustment
means typically comprises an inflatable cavity in the band and
an injection port in fluid connection with the inflatable cavity
for adding fluid to or withdrawing fluid from the latter. In
practice, the band is made of silicone rubber which is a material
approved for implantation and the fluid is a liquid such as an
isotonic salt solution.
It has also been found that the volume of the gastric pouch
above the band increases in size up to ten times after operation.
Therefore the pouch volume during surgery needs to be very small,
approximately 7 ml. To enable the patient to feed the, stomach
with sufficient nutrition immediately after an operation
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considering such a small gastric pouch, the stoma initially needs
to be relatively large and later needs to be substantially
reduced, as the pouch volume increases. To be able to achieve a
significant range of adjustment of the band, the cavity in the
band has to be relatively large and is defined by a thin flexible
wall, normally made of silicone material. Furthermore, the size
of the stoma opening has to be gradually reduced during the.first
year after surgery as the gastric pouch increases in size. As
indicated above, the reduction of the stoma opening using the
prior art devices is achieved by adding liquid to the cavity of
the band via the injection port to expand the band radially
inwardly.
A great disadvantage of repeatedly injecting liquid via the
injection port is the increased risk of the patient getting an
infection in the body area surrounding the injection port. If
such an infection occurs the injection port has to be surgically
removed from the patient. Moreover, such an infection might be
spread along the tube interconnecting the injection port and the
band to the stomach, causing even more serious complications.
Thus, the stomach might be infected where it is in contact with
the band, which might result in the band migrating through the
wall of the stomach. Also, it is uncomfortable for the patient
when the necessary, often many, post-operation adjustments of the
stoma opening are carried out using an injection needle
penetrating the skin of the patient into the injection port.
It may happen that the patient swallows pieces of food too
large to pass through the restricted stoma opening. If that
occurs the patient has to visit a doctor who can remove the food
pieces, if the band design so permits, by withdrawing some liquid
from the band to enlarge the stoma opening to allow the food
pieces to pass the stoma. Then, the doctor has to add liquid to
the band in order to regain the restricted stoma opening. Again,
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these measures require the use of an injection needle penetrating
the skin of the patient, which is uncomfortable for the patient.
An object of the invention is to provide a food intake
restriction apparatus for forming a stoma opening in the stomach
or esophagus of a patient which permits regular post-operation
adjustments that are comfortable for the patient.
Another object of the present invention is to provide a food
intake restriction apparatus which is easy to adjust and does not
require the use of an injection needle for accomplishing post-
operation adjustments of the stoma opening.
These objects are achieved by a food intake restriction
apparatus of the kind stated initially, which is characterised
in that the restriction device is operable to change the
restriction of the stoma opening, a source of energy is provided,
and a control device operable from outside the patient's body is
provided for controlling the source of energy to release energy
for use in connection with the operation of the restriction
device, when the restriction device is implanted.
As a result, the advantage is achieved that the restriction
device can be non-invasively operated, when the restriction
device has tobe adjusted. Furthermore, the apparatus of the
invention provides a simple and effective control of the energy
supplied to implanted components of the apparatus which ensures
an extended and reliable functionality of the apparatus, possibly
for the rest of the patient's life and at least many years.
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Accordingly, in one embodiment, the present invention
provides a food intake restriction apparatus for an obese
patient. The apparatus includes an operable restriction
device, a source of energy external to the patient's body,
a control device and an energy transfer device. The
operable restriction device is adapted to be implanted in
the patient to engage the stomach or esophagus to form an
upper pouch of the stomach and a restricted stoma opening
in the stomach or esophagus. The source of energy is
external to the patient's body. The control device is
operable from outside the patient's body for releasing
wireless energy from the source of energy for use in the
operation of the restriction device to vary the restricted
stoma opening. The energy transfer device is adapted to be
implanted in the patient, for transferring the wireless
energy into a different form of energy useable by the
operable restriction device.
The control device may control the restriction device.
The control device may comprise an internal control unit,
preferably including a microprocessor, implantable in the patient
for controlling the restriction device. The control device may
further comprise an external control unit outside the patient's
body, wherein the internal control unit is programmable by the
DOCSTOR: 1391632\1
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external control unit, for example for controlling the
restriction device over time. Alternatively, the internal control
unit may control the restriction device over time in accordance
with an activity schedule program, which may be adapted to the
patient's needs.
A great advantage is that the patient is enabled to adjust
the restriction of the stoma opening by using the control device
whenever he likes during the day. This advantage should not be
underestimated, because in case the patient would need to vomit
it would be very difficult for him to do so if he were unable to
immediately enlarge the stoma opening.
Conveniently, the external control unit may load the
internal control unit with data in accordance with a loading mode
only authorized for a doctor. For specialized controls of the
restriction device, the external control unit may control the
internal control unit in accordance with a doctor mode only
authorized for the doctor. For simple controls of the restriction
device, the external control unit may control the internal
control unit in accordance with a patient mode permitted for the
patient. Thus, by using the external control unit in accordance
with different modes it is possible to have certains functions
of the restriction device controlled by the patient and other
more advanced functions controlled by the doctor, which enables
a flexible post-operation treatment of the patient.
The control device may be adapted to control the source of
energy to release energy, for instance to intermittently release
energy in the form of a train of energy pulses, for direct use
in connection with the operation of the restriction device. In
accordance with a suitable embodiment the control device controls
the source of energy to release electric energy, and the
apparatus further comprises an implantable capacitor for
producing the train of energy pulses from the released energy.
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In this case the term "direct" is used to mean, on one hand, that
the released energy is used while it is being released by the
control device, on the other hand, that the released energy may
be somewhat delayed, in the.order of seconds, by for instance an
5 energy stabiliser before being used in connection with the
operation of the restriction device. The restriction device may
be operable in non-manual, a non-magnetic or non-mechanical
manner by use of the released energy.
In accordance with a preferred embodiment of the invention,
the apparatus comprises implantable electrical components
including at least one, or only one single voltage level guard
and a capacitor or accumulator, wherein the charge and discharge
of the capacitor or accumulator is controlled by use of the
voltage level guard. As a result, there is no need for any
implanted current detector and/or charge level detector for the
control of the capacitor, which makes the apparatus simple and
reliable.
Generally, the apparatus further comprises an operation
device implantable in the patient for operating the restriction
device, wherein the control device controls the operation device
to operate the restriction device. The control device may
directly power the operation device with energy released from the
source of energy and/or power other implantable energy consuming
components of the apparatus. In this case the term "directly" is
used to mean, on one hand, that the operation device is powered
with released energy while the latter is being released by the
control device, on the other hand, that the released energy may
be somewhat delayed, in the order of seconds, by for instance an
energy stabiliser before powering the operation device. The
advantage of directly using energy as it is released is that the
apparatus can be of a very simple design and the few components
involved makes the apparatus reliable.
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The restriction device may be non-inflatable, i.e. with no
hydraulic fluid involved for the adjustments of the restriction
device. This eliminates problems with fluid leaking from the
restriction device.
The operation device may comprise hydraulic means and at
least one valve for controlling a fluid flow in the hydraulic
means. The control device may suitably comprise a wireless remote
control for controlling the valve. The restriction device may
comprise hydraulic means and the operation device may comprise
a reservoir forming a fluid chamber with a variable volume
connected to the hydraulic means. The operation device may
distribute fluid from the chamber to the hydraulic means by
reduction of the volume of the chamber and withdraw fluid from
the hydraulic means to the chamber by expansion of the volume of
the chamber.
In accordance with a first main aspect of the invention, the
source of energy is external to the patient's body and the
control device controls the source of energy to release wireless
energy. The external source of energy may be of any conceivable
kind, such as a nuclear source of energy or a chemical source of
energy.
An energy storage device, preferably an electric
accumulator, may be implantable in the patient for storing the
wireless energy released from the external source of energy. The
electric accumulator may comprise at least one capacitor or at
least one rechargeable battery, or a combination of at least one
capacitor and at least one rechargeable battery. Alternatively,
a battery may be implantable in the patient for supplying
electric energy to implanted electric energy consuming
components of the apparatus, in addition to the supply of
wireless energy. Where the control device comprises an
implantable control unit the electronic circuit thereof and the
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restriction device may be directly powered with transformed
wireless energy, or energy from either the implantable energy
storage device or battery.
In accordance with a second main aspect of the invention,
the wireless energy is directly used for operation of the
restriction device, i.e. the restriction device is operated as
the wireless energy is released from the external source of
energy by the control device. In this case the term "directly"
is used to mean, on one hand, that the restriction device is
promptly operated by using the released energy whithout first
storing the latter, on the other hand, that the released energy
may be somewhat delayed, in the order of seconds, by for instance
an energy stabiliser before being used for the operation of the
restriction device. As a result, a very simple control of the
restriction device is achieved and there are only a few implanted
components of the apparatus. For example, there is no implanted
source of energy, such as a battery, nor any implanted
complicated signal control system. This gives the advantage that
the apparatus will be extremely reliable.
Generally, the control device controls and directly or
indirectly powers the operation device with wireless energy
released from the source of energy and/or powers other implanted
energy consuming components of the apparatus.
In a first particular embodiment in accordance with the
first and second main aspects of the invention, the operation,
device comprises a motor, preferably an electric motor which may
have electrically conductive parts made of plastics. The motor
may include a rotary motor, wherein the control device is adapted
to control the rotary motor to rotate a desired number of
revolutions. Alternatively, the motor may include a linear motor,
or a hydraulic or pneumatic fluid motor, wherein the control
device is adapted to control the fluid flow through the fluid
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motor. Motors currently available on the market are getting
smaller and smaller. Furthermore, there is a great variety of
control methods and miniaturized control equipment available. For
example, a number of revolutions of a rotary motor may be
analyzed by a Hall-element just a few mm in size.
In a second particular embodiment in accordance with the
first. and second main aspects of the invention, the control
device is adapted to shift polarity of the released energy to
reverse the operation device. The operation device may suitably
comprise an electric motor and the released energy may comprise
electric energy.
In a third particular embodiment in.accordance with the
first and second main aspects of the invention, the restriction
device is operable to perform a reversible function and there is
a reversing device implantable in the patient for reversing the
function performed by the restriction device. Such a reversing
function preferably involves enlarging and restricting the stoma
opening by the restriction device, suitably in a stepless manner.
In this connection, the control device suitably controls the
reversing device, which may include a switch, to reverse the
function performed by the restriction device. The reversing
device may comprise hydraulic means including a valve for
shifting the flow direction of a fluid in the hydraulic means.
Alternatively, the reversing device may comprise a mechanical
reversing device, such as a switch or a gearbox.
Where the reversing device comprises a switch the control
device suitably controls the operation of the switch by shifting
polarity of released energy supplied to the switch. The switch
may comprise an electric switch and the source of energy may
supply electric energy for the operation of the switch. The
switch mentioned above may comprise an electronic switch or,
where applicable, a mechanical switch.
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In accordance with the third particular embodiment, the
operation device preferably comprises a motor, wherein the
reversing device reverses the motor.
In a fourth particular_embodiment in accordance with the
first and second main aspects of the invention, the restriction
device comprises hydraulic means, for example including an
expansible/contractible cavity for hydraulic fluid. Preferably,
the operation device is adapted to conduct hydraulic fluid in the
hydraulic means, and comprises a motor, a valveless fluid conduit
connected to the hydraulic means of the restriction device, and
a reservoir for fluid, wherein the reservoir forms part of the
conduit. The operation device suitably comprises a pump operated
by the motor. All of the hydraulic components involved are
preferably deviod of any non-return valve. This is of great
advantage, because with valves involved there is always a risk
of malfunction due to inproperly working valves, especially when
long time periods passes between valve operations. The reservoir
may form a fluid chamber with a variable volume, and the pump may
distribute fluid from the chamber to the hydraulic means of the
restriction device by reduction of the volume of the chamber and
withdraw fluid from the hydraulic means to the chamber by
expansion of the volume of the chamber.
In accordance with a third main aspect of the invention, the
source of energy is implantable in the patient. Thus, when the
source of energy is implanted in a patient the control device
controls it from outside the patient's body to release energy.
This solution is advantageous for embodiments of the apparatus
that have a relatively high consumption of energy which cannot
be satisfied by direct supply of wireless energy.
The implantable source of energy may comprise an
accumulator, preferably an electric source of energy, such as a
battery having a lifetime of at least 10 years.
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In accordance with a fourth main aspect of the invention,
the apparatus comprises a switch implanted in the patient for
directly or indirectly switching the operation of the restriction
device and an internal source of energy, such as a battery,
5 implanted in the patient for supplying energy for the operation
of the restriction device, wherein the switch directly or
indirectly affects the supply of energy from the internal source
of energy. This solution is advantageous for embodiments of the
apparatus that have a relatively high energy consumption which
10 cannot be met by direct supply of wireless.energy.
In a first particular embodiment in accordance with the
fourth main aspect of the invention, the switch switches between
an off mode, in which the internal source of energy is not in
use, and an on mode, in which the internal source of energy
supplies energy for the operation of the restriction device. In
this case, the switch is conveniently operated by the wireless
energy released from the external source of energy to switch
between the on and off modes. The control device, preferably
comprising a wireless remote control, may control the external
source of energy to release the wireless energy. The advantage
of this embodiment is that the lifetime of the implanted source
of energy, such as a battery, can be significantly prolonged,
since the implanted source of energy does not supply energy when
the switch is in its off mode.
In a second particular embodiment in accordance with the
fourth main aspect of the invention, the control device comprises
a wireless remote control for controlling the internal source of
energy. In this case, the switch is operable by the wireless
energy from the external source of energy to switch between an
off mode, in which the internal source of energy and remote
control are not in use, and a standby mode, in which the remote
control is permitted to control the internal source of energy to
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supply energy for the operation of the restriction device.
In a third particular embodiment in accordance with the
fourth main aspect of the invention, the apparatus further
comprises an energy transforming device implanted in the patient
for transforming the wireless energy into storable energy,
wherein the internal source of energy is capable of storing the
storable energy. The internal source of energy preferably
comprises an electric accumulator, at least one capacitor or at
least one rechargeable battery, or a combination of at least one
capacitor and at least one rechargeable battery. In this case,
the switch switches from an off mode, in which the internal
source of energy is not in use, to an on mode, in which the
internal source of energy supplies energy for the operation of
the restriction device.
The control device, preferably comprising a wireless remote
control, may control the switch to switch between the on and off
modes.
Alternatively, in this third particular embodiment an energy
storage device may be implanted in the patient for storing the
storable energy instead of the internal source of energy, wherein
the switch is operable by energy from the implanted energy
storage device to switch between an off mode, in which the
internal source of energy is not in use, and an on mode, in which
the internal source of energy supplies energy for the operation
of the restriction device. In this case, the control device (the
wireless remote control) controls the energy storage device to
operate the switch.
The internal source of energy preferably comprises an
electric source of energy, such as an accumulator or a battery
having a lifetime of at least 10 years. However, other kinds of
sources are also conceivable, such as a nuclear source of energy
or a chemical source of energy.
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The above first, second, third and fourth particular
embodiments described in connection with the first and second
main aspects of the invention are also applicable in accordance
with the third main aspect of the invention, i.e. where the
source of energy is implantable, and in accordance with the
fourth main aspect of the invention, i.e. where the apparatus
comprises an implantable switch.
All of the above embodiments may be combined with at least
one implantable sensor for sensing at least one physical
parameter of the patient, wherein the control device may control
the restriction device in response to signals from the sensor.
For example, the sensor may comprise a pressure sensor for
directly or indirectly sensing the pressure in the stomach or
esophagus. The expression "indirectly sensing the pressure in the
stomach or esophagus" should be understood to encompass the cases
where the sensor senses the pressure against the restriction
device or human tissue of the patient. Where the control device
comprises an internal control unit to be implanted in the
patient, the internal control unit may suitably directly control
the restriction device in response to signals from the sensor.
In response to signals from the sensor, for example pressure, the
patient's position or any other important physical parameter, the
internal control unit may send information thereon to outside the
patient's body. The control unit may also automatically'control
the restriction device in response to signals from the sensor.
For example, the control unit may control the restriction device
to further restrict the stoma opening in the stomach in response
to the sensor sensing that the patient is lying, or enlarge the
stoma opening in response to the sensor sensing an abnormally
high pressure against the restriction device.
Where the control device comprises an external control unit
outside the patient's body, the external control unit may,
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suitably directly, control the restriction device in response to
signals from the sensor. The external control unit may store
information on the physical parameter sensed by the sensor and
may be manually operated to control the restriction device based
on the stored information. In addition, there may be at least one
implantable sender for sending information on the physical
parameter sensed by the sensor.
An external data communicator may be provided outside the
patient's body and an internal data communicator to be implanted
in the patient may be provided for communicating with the
external data communicator. The internal data communicator may
feed data related to the patient, or related to the restriction
device, back to the external data communicator. Alternatively or
in combination, the external data communicator may feed data to
the internal data communicator. The internal data communicator
may suitably feed data related to at least one physical signal
of the patient.
Generally, the apparatus of the invention may comprise, a
switch implantable in the patient for directly or indirectly
switching the energy released from the source of energy. For
example, the restriction device may be operable to open and close
the stoma opening or may steplessly control the size of the stoma
opening. A pressure sensor may be provided for directly or
indirectly sensing the pressure in the stomach or esophagus. The
control device may control the restriction device in response to
signals from the pressure sensor.
The apparatus may 'comprise an implantable energy
transforming device, wherein the control device releases electric
energy and the energy transforming device transforms the
electric energy into kinetic energy for, preferably direct,
operation of the restriction device. Suitably, an implantable
stabiliser, such as a capacitor or a rechargeable accumulator,
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or the like, may be provided for stabilising the electric energy
released by the control device. In addition, the control device
may control the source of energy to release energy for a
determined time period or in a determined number of energy
pulses. Finally, the restriction device may be non-inflatable.
All of the above embodiments are preferably remote
controlled. Thus, the control device advantageously comprises a
wireless remote control transmitting at least one wireless
control signal for controlling the restriction device. With such
a remote control it will be possible to adapt the function of the
apparatus to the patient's need in a daily basis, which is
beneficial with respect to the treatment of the patient.
The wireless remote control may be capable of obtaining
information on the condition of the restriction device and of
controlling the restriction device in response to the
information. Also, The remote control may be capable of sending
information related to the restriction device from inside the
patient's body to the outside thereof.
In a particular embodiment of the invention, the wireless
remote control comprises at least one external signal transmitter
or transceiver and at least one internal signal receiver or
transceiver implantable in the patient. In another particular
embodiment of the invention, the wireless remote control
comprises at least one external signal reciever or transceiver
and at least one internal signal transmitter or transceiver
implantable in the patient.
The remote control may transmit a carrier signal for
carrying the control signal, wherein the carrier signal is
frequency, amplitude or frequency and amplitude modulated and is
digital, analog or digital and analog. Also the control signal
used with the carrier signal may be frequency, amplitude or
frequency and amplitude modulated.
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The control signal may comprise a wave signal, for example,
a sound wave signal, such as an ultrasound wave signal, an
electromagnetic wave signal, such as an infrared light signal,
a visible light signal, an ultra violet light signal, a laser
5 signal, a micro wave signal, a radio wave signal, an x-ray
radiation signal, or a gamma radiation signal. Where applicable,
two or more of the above signals may be combined.
The control signal may be digital or analog, and may
comprise an electric or magnetic field. Suitably, the wireless
10 remote control may transmit an electromagnetic carrier wave
signal for carrying the digital or analog control signal. For
example, use of an analog carrier wave signal carrying a digital
control signal would give safe communication. The control signal
may be transmitted in pulses by the wireless remote control.
15 In all of the above solutions, the control device
advantageously releases energy from the source of energy in a
non-invasive, magnetic, non-magnetic, mechanical or non-
mechanical manner.
The control device may release magnetic, electromagnetic,
kinetic, sonic or thermal energy, or non-magnetic, non-sonic,
non-thermal, non-electromagnetic or non-kinetic energy.
The control device may be activated in a manual or non-
manual manner to control the source of energy to release energy.
The operation device may be powered by magnetic energy, non-
magnetic energy, electromagnetic energy, non-electromagnetic
energy, kinetic energy, non-kinetic energy, thermal energy or
non-thermal energy. However, preferably the operation device
comprises an electrical operation device.
Typically the apparatus of the invention comprises an
adjustment device for adjusting the restriction device to change
the size of the stoma opening. The adjustment device may be
adapted to mechanically adjust the restriction device.
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Alternatively, the adjustment device may be adapted to
hydraulically adjust the restriction device by using hydraulic
means which is devoid of hydraulic fluid of the kind having a
viscosity that substantially increases when exposed to heat or
a magnetic field, i.e. the hydraulic fluid would not become more
viscous when exposed to heat or influenced by magnetic forces.
The above-presented embodiments of the invention may be
modified in accordance with the following suggestions. The
released energy may comprise electric energy and an implantable
capacitorhaving a capacity less than 0,1 F may be provided for
producing the above-mentioned train of energy pulses.
An implantable motor or pump may be provided for operating
the restriction device, wherein the control device is adapted to
control the source of energy to directly power the motor or pump
with the released energy. Specifically, the control device may
be adapted to release wireless energy in the form of a magnetic
field or electromagnetic waves (excluding radio waves) for direct
power of the motor or pump, as the wireless energy is being
released. Where a pump is used it preferably is not a plunger
type of pump.
Generally, the wireless energy comprises a signal.
The apparatus may further comprise implantable energy
transforming device for transforming wireless energy directly or
indirectly into energy different than the wireless energy, for
operation of the restriction device. For example, the motor or
pump may be powered by the transformed energy.
The energy transforming device may transform the wireless
energy in the form of sound waves, preferably directly, into
electric energy for operation of the restriction device. The
energy transforming device may comprise a capacitor adapted to
produce electric pulses from the transformed electric energy.
The motor mentioned in the present specification may also
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be directly powered-with wirelessly transmitted electromagnetic
or magnetic energy in the form of signals, as the energy is
transmitted. Furthermore, all the various functions of the motor
and associated components described in the present specification
may be used where applicable.
Generally, the restriction device advantageously is embedded
in a soft or gel-like material, such as a silicone material
having hardness less than 20 Shore.
Of course, the restriction device preferably is adjustable
in a non-manual manner.
All the above described various components, such as the
motor, pump and capacitor, may be combined in the different
embodiments where applicable. Also the various functions
described in connection with the above embodiments of the
invention may be used in different applications, where
applicable.
All the various ways of transferring energy and controlling
the energy presented in the present specification may be
practised by using all of the various components and solutions
described.
The present invention also provides methods for treating
obese patients.
Accordingly, in accordance with a first alternative method,
there is provided a method of treating an obese patient,
comprising the steps of implanting an operable restriction device
in the patient, so that the restriction device engages the
stomach or esophagus to form an upper pouch of the stomach and
a restricted stoma opening in the stomach or esophagus, providing
a source of energy for energizing the restriction device, and
controlling the source of energy to release energy for use in
connection with the operation of the restriction device. The
method may further comprise using energy released from the source
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of energy to operate the restriction device to enlarge and
reduce, respectively, the stoma opening.
In accordance with a second alternative method, there is
provided a method of treating an obese patient, comprising the
steps of placing at least two laparascopical trocars in the
patient's body, inserting a dissecting tool through the trocars
and dissecting an area of the stomach or esophagus, placing an
operable restriction device in the dissected area, so that the
restriction device engages the stomach or esophagus to form a
stoma opening in the stomach or esophagus, implanting a source
of energy in the patient, and controlling the implanted source
of energy from outside the patient's body to release energy for
use in connection with the operation of the restriction device.
In accordance with a third alternative method, there is
provided a method of treating an obese patient, comprising: (a)
Surgically implanting in the patient an operable restriction
device engaging the patient's stomach or esophagus to form a
stoma opening in the stomach or esophagus. (b) Providing a source
of energy external to the patient's body. (c). Controlling the
external source of energy from outside the patient's body to
release wireless energy. And (d) using the released wireless
energy in connection with the operation of the restriction
device.
In accordance with a fourth alternative method, there is
provided a method of treating an obese patient, comprising the
steps of placing at least two laparascopical trocars in the
patient's body, inserting a dissecting tool through the trocars
and dissecting an area of the stomach or esophagus, placing an
operable restriction device in the dissected area, so that the
restriction device engages the stomach-or esophagus to form a
stoma opening in the stomach or esophagus, providing an external
source of energy outside the patient's body, controlling the
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external source of energy from outside the patient's body to
release wireless energy, and using the released wireless energy
in connection with the operation of the restriction device.
In accordance with a fifth alternative method, there is
provided a method of treating an obese patient, comprising the
steps of placing at least two laparascopical trocars in the
patient's body, inserting a dissecting tool through the trocars
and dissecting an area of the stomach or esophagus, implanting
an operable restriction device in the dissected area, so that the
restriction device engages the stomach or esophagus to form a
stoma opening in the stomach or esophagus, implanting an energy
transforming device, providing an external source of energy,
controlling the external source of energy to release wireless
energy, and transforming the wireless energy by the energy
transforming device into energy different from the wireless
energy for use in connection with the operation of the
restriction device. This method may further comprise implanting
a stabiliser in the patient for stabilising the energy
transformed by the energy transforming device.
The invention is described in more detail in the following
with reference to the accompanying drawings, in which
FIGURES 1 to 6 are schematic block diagrams illustrating six
embodiments, respectively, of the invention, in which wireless
energy is released from an external source of energy;
FIGURES 7 to 10 are schematic block diagrams illustrating
four embodiments, respectively, of the invention, in which energy
is released from an implanted source of energy;
FIGURES 11 to 15 are schematic block diagrams illustrating
five embodiments, respectively, of the invention, in which a
switch is implanted in the patient for directly or indirectly
switching the operation of the restriction device;
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FIGURE 16 is a schematic block diagram illustrating
conceivable combinations of implantable components for achieving
various communication options;
FIGURE 17 illustrates the apparatus in accordance with the
5 invention implanted in a patient;
FIGURE 18 is a block diagram illustrating remote control
components of an embodiment of the invention; and
FIGURE 19 is a schematic view of exemplary circuitry used
for the components of the block diagram of FIGURE 18.
10 Referring to the drawing figures, like reference numerals
designate identical or corresponding elements throughout the
several figures.
FIGURE 1 schematically shows an embodiment of the food
15 intake restriction apparatus of the invention having some parts
implanted in a patient and other parts located outside the
patient's body. Thus, in FIGURE 1 all parts placed to the right
of the patient's skin 2 are implanted and all parts placed to the
left of the skin 2 are located outside the patient's body. The
20 apparatus of FIGURE 1 comprises an implanted operable restriction
device 4, which engages the patient's stomach (or alternatively
engages the esophagus) to form a stoma opening in the stomach.
The restriction device 4 is capable of performing a reversible
function, i.e. to enlarge and reduce the stoma opening. An
implanted control unit 6 controls the restriction device 4 via
a control line 8 to form an adequate size of the of the stoma
opening. An external control unit 10 includes an external source
of energy and a wireless remote control transmitting a control
signal generated by the external source of energy. The control
signal is received by a signal receiver incorporated in the
implanted control unit 6, whereby the control unit 6 controls the
implanted restriction device 4 in response to the control signal.
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The implanted control unit 6 also uses energy from the control
signal for operating the restriction device 4 via a power supply
line 12.
FIGURE 2 shows an embodiment of the invention identical to
that of FIGURE 1, except that a reversing device in the form of
a switch 14 operable by energy also is implanted in the patient
for reversing the restriction device 4. The control unit 6 uses
the switch 14 to reverse the function performed by the
restriction device 4. More precisely, the external control unit
10 releases energy carried by a wireless signal and the implanted
control unit 6 transforms the wireless energy into a current for
operating the switch 14. When the control unit 6 shifts the
polarity of the current the switch 14 reverses the function
performed by the restriction device 4.
FIGURE 3 shows an embodiment of the invention identical to
that of FIGURE 1, except that an operation device in the form of
a motor 16 also is implanted in the patient. The implanted
control unit 6 powers the motor 16 with wireless energy released
from the external source of energy of the external control unit
10. The implanted control unit 6 controls the operation of the
motor 16 in response to a control signal from the remote control
of the external control unit 10.
FIGURE 4 shows an embodiment of the invention identical to
that of FIGURE 1, except that an assembly 16 including a
motor/pump unit 18 and a fluid reservoir 20 also is implanted in
the patient. In this case the restriction device 4 is
hydraulically operated, i.e. hydraulic fluid is pumped by the
motor/pump unit 18 from the reservoir 20 through a conduit 22 to
the restriction device 4 to restrict the stoma opening, and
hydraulic fluid is pumped by the motor/pump unit 18 back from the
restriction device 4 to the reservoir 20 to enlarge the stoma
opening. The external control unit 10 releases energy carried by
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a wireless signal and the implanted control unit 6 transforms the
wireless energy into a current, for example a current, for
powering the motor/pump unit 18 via an electric power supply line
24. The implanted control unit 6 controls the motor/pump unit 16
and the restriction device 4 via control lines 26 and 27.
FIGURE 5 shows an embodiment of the invention comprising the
restriction device 4, hydraulically operated, and the implanted
control unit 6, and further comprising a hydraulic fluid
reservoir 230, a motor/pump unit 232 and a reversing device in
the form of a hydraulic valve shifting device 234, all of which
are implanted in the patient. The motor of the motor/pump unit
232 is an electric motor.
FIGURE 6 shows an embodiment of the invention identical to
that of FIGURE 1, except that an accumulator 28 also is implanted
in the patient. The control unit 6 stores energy received from
the external control unit 10 in the accumulator 28. In response
to a control signal from the external control unit 10 the
implanted control unit 6 releases energy from the accumulator 28
via a power line 30 for the operation of the restriction device
4.
FIGURE 7 shows an embodiment of the invention comprising the
restriction device 4, hydraulically operated, and the implanted
control unit 6, and further comprising a source of energy in the
form of a battery 32, a hydraulic fluid reservoir 34, a
motor/pump unit 36 and a reversing device in the form of a
hydraulic valve shifting device 38, all of which are implanted
in the patient. The motor of the motor/pump unit 36 is an
electric motor. An external control unit 40 includes a wireless
remote control transmitting a control signal which is received
by the signal receiver incorporated in the implanted control unit
6.
In response to a control signal from the external control
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unit 40 the implanted control unit 6 powers the motor/pump unit
36 with energy from the battery 32, whereby the motor/pump unit
36 distributes hydraulic fluid between the reservoir 34 and the
restriction device 4. The control unit 6 controls the shifting
device 38 to shift the hydraulic fluid flow direction between one
direction in which the fluid is pumped by the motor/pump unit 36
from the reservoir 34 to the restriction device 4 to restrict the
stoma opening, and another opposite direction in which the fluid
is pumped by the motor/pump unit 36 back from the restriction
device 4 to the reservoir 34 to enlarge the stoma opening.
FIGURE 8 shows an embodiment of the invention identical to
that of FIGURE 6, except that a battery 42 is substituted for the
accumulator 28, the external control unit 40 of the embodiment
of FIGURE 5 is substituted for the external control unit 10 and
an electric motor 44 is implanted in the patient for operating
the restriction device 4. In response to a control signal from
the external control unit 40 the implanted control unit 6 powers
the motor 44 with energy from the battery 42, whereby the motor
44 operates the restriction device 4.
FIGURE 9 shows an embodiment of the invention identical to
that of FIGURE 8, except that the motor/pump unit 36 of the
embodiment of FIGURE 7 is substituted for the motor 44 and a
fluid reservoir 46 also is implanted in the patient. The
reservoir 46 is via fluid conduits 48 and 50 connected to the
motor/pump unit 36 and restriction device 4, which in this case
is hydraulically operated. In response to a control signal from
the external control unit 40, the implanted control unit 6 powers
the electric motor of the motor/pump unit 36 with energy from the
battery 42, whereby the motor/pump unit 36 distributes hydraulic
fluid between the fluid reservoir 46 and the restriction device
4.
FIGURE 10 shows an embodiment of the invention identical to
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that of FIGURE 8, except that a mechanical reversing device in
the form of a gearbox 52 also is implanted in the patient. The
implanted control unit 6 controls the gearbox 52 to reverse the
function performed by the restriction device 4 (mechanically
operated).
FIGURE 11 shows an embodiment of the invention comprising
the restriction device 4, the external control unit 10, an
implanted source of energy 236 and an implanted switch 238. The
switch 238 is operated by wireless energy released from the
external source of energy of the external control unit 6 to
switch between an off mode, in which the implanted source of
energy 236 is not in use, and an on mode, in which the implanted
source of energy 236 supplies energy for the operation of the
restriction device 4.
FIGURE 12 shows an embodiment of the invention identical to
that of FIGURE 11, except that also the control unit 6 is
implanted, in order to receive a control signal from the wireless
remote control of the external control unit 10. The switch 238
is operated by the wireless energy from the external source of
energy 10 to switch between an off mode, in which the implanted
source of energy 236 and the wireless remote control of the
external control unit 10 are not in use, i.e. the control unit
6 is not capable of receiving the control signal, and a standby
mode, in which the wireless remote control is permitted to
control the internal source of energy 236, via the implanted
control unit 6, to supply energy for the operation of the
restriction device 4.
FIGURE 13 shows an embodiment of the invention identical to
that of FIGURE 12, except that an energy transforming device for
transforming the wireless energy into storable energy is
incorporated in the implanted control unit 6 and that the
implanted source of energy 236 is of a type that is capable of
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storing the storable energy. In this case, in response to a
control signal from the external control unit 10, the implanted
control unit 6 controls the switch. 238 to switch from an o.ff
mode, in which the implanted source of energy 236 is not in use,
5 to an on mode, in which the source of energy 36 supplies energy
for the operation of the restriction device 4.
FIGURE 14 shows an embodiment of the invention identical to
that of FIGURE 13, except that an energy storage device 240 also
is implanted in the patient for storing the storable energy
10 transformed from the wireless energy by the transforming device
of the control unit 6. In this case, the implanted ontrol unit
6 controls the energy storage device 240 to operate the switch
238 to switch between an off mode, in which the implanted source
of energy 236 is not in use, and an on mode, in which the
15 implanted source of energy 236 supplies energy for the operation
of the restriction device 4.
FIGURE 15 shows an embodiment of the invention identical to
that of FIGURE 13, except that a motor 242 and a mechanical
reversing device in the form of a gearbox 244 also are implanted
20 in the patient. The implanted control unit 6 controls thegearbox
244 to reverse the function performed by the restriction device
4 (mechanically operated), i.e. enlarging and restricting the
stoma opening.
FIGURE 16 schematically shows conceivable combinations of
25 implanted components of the apparatus for achieving various
communication possibilities. Basically, there are the implanted
restriction device 4, the implanted control unit 6 and the
external control unit 10 including the external source of energy
and the wireless remote control. As already described above the
remote control transmits a control signal generated by the
external source of energy, and the control signal is received by
a signal receiver incorporated in the implanted control unit 6,
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whereby the control unit 6 controls the implanted restriction
device 4 in response to the control signal.
A sensor 54 may be implanted in the patient for sensing a
physical parameter of. the patient, such as the pressure in the
stomach. The control unit 6, or alternatively the external
control unit 10, may control the restriction device 4 in response
to signals from the sensor 54. A transceiver may be combined with
the sensor 54 for sending information on the sensed physical
parameter to the external control unit 10. The wireless remote
control of the external control unit 10 may comprise a signal
transmitter or transceiver and the implanted control unit 6 may
comprise a signal receiver or transceiver. Alternatively, the
wireless remote control of the external control unit 10 may
comprise a signal receiver or transceiver and the implanted
control unit 6 may comprise a signal transmitter or transceiver.
The above transceivers, transmitters and receivers may be used
for sending information or data related to the restriction device
from inside the patient's body to the outside thereof.
The motor 44 may be implanted for operating the restriction
device 4 and also the battery 32 may be implanted for powering
the motor 44. The battery 32 may be equipped with a transceiver
for sending information on the charge condition of the battery.
Those skilled in the art will realize that the above various
embodiments according to FIGURES 1-15 could be combined in many
different ways. For example, the energy operated switch 14 could
be incorporated in any of the embodiments of FIGURES 4,6,8-10.
The hydraulic shifting device 38 could be incorporated in any of
the embodiments of FIGURES 4 and 9. The gearbox 52 could be
incorporated in any of the embodiments of FIGURES 1,6 and 8.
FIGURE 17 illustrates how any of the above-described
embodiments of the apparatus of the invention may be implanted
in a patient. Thus, an assembly of the apparatus implanted in the
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patient comprises a restriction device 56 engaging the esophagus
58 and a portion of the stomach, so that an upper pouch 60 of the
stomach is formed, an operation device 61 for operating the
restriction device 56 and an. internal control unit 62, which
includes a signal receiver, for controlling the operation device
61. An external control unit 64 includes a signal transmitter for
transmitting a wireless control signal to the signal receiver of
the implanted control unit 62. The implanted control unit 62 is
capable of transforming signal energy from the control signal
into electric energy for powering the operation device 61 and for
energizing energy consuming implanted components of the
apparatus.
FIGURE 18 shows the basic parts of a wireless remote control
of the apparatus of the invention including an electric motor 128
for operating a restriction member, for example of the type
illustrated in FIGURE 17. In this case, the remote control is
based on the transmission of electromagnetic wave signals, often
of high frequencies in the order of 100 kHz - 1 gHz, through the
skin 130 of the patient. In FIGURE 18, all parts placed to the
left of the skin 130 are located outside the patient's body and
all parts placed to the right of the skin 130 are implanted . Any
suitable remote control system may be used.
An external signal transmitting antenna 132 is to be
positioned close to a signal receiving antenna 134 implanted
close to the skin 130. As an alternative, the receiving antenna
134 may be placed for example inside the abdomen of the patient.
The receiving antenna 134 comprises a coil, approximately 1-100
mm, preferably 25 mm in diameter, wound with a very thin wire
and tuned with a capacitor to a specific high frequency. A small
coil is chosen if it is to be implanted under the skin of the
patient and a large coil is chosen if it is to be implanted in
the abdomen of the patient. The transmitting antenna 132
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comprises a coil having about the same size as the coil of the
receiving antenna 134 but wound with a thick wire that can handle
the larger currents that is necessary. The coil of the
transmitting antenna 132 is tuned to the same specific high
frequency as the coil of the receiving antenna 134.
An external control unit 136 comprises a microprocessor, a
high frequency electromagnetic wave signal generator and a power
amplifier. The microprocessor of the control unit 136 is adapted
to switch the generator on/off and to modulate signals generated
by the generator to send digital information via the power
amplifier and the antennas 132,134 to an implanted control unit
138. To avoid that accidental random high frequency fields
trigger control commands, digital signal codes are used. A
conventional keypad placed on the external control unit 136 is
connected to the microprocessor thereof. The keypad is used to
order the microprocessor to send digital signals to either
contract or enlarge the restriction device. The microprocessor
starts a command by applying a high frequency signal on the
antenna 132. After a short time, when the signal has energized
the implanted parts of the control system, commands are sent to
contract or enlarge the restriction device in predefined steps.
The commands are sent as digital packets in the form illustrated
below.
Start pattern, Command, Count, Checksum,
8 bits 8 bits 8 bits 8 bits
The commands are sent continuously during a rather long time
period (e.g. about 30 seconds or more). When a new contract or
enlarge step is desired the Count byte is increased by one to
allow the implanted control unit 138 to decode and understand
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that another step is demanded by the external control unit 136.
If any part of the digital packet is erroneous, its content is
simply ignored.
Through a line 140, an implanted energizer unit 126 draws
energy from the high frequency electromagnetic wave signals
received by the receiving antenna 134. The energizer unit 126
stores the energy in a power supply, such as a large capacitor,
powers the control unit 138 and powers the electric motor 128 via
a line 142.
The control unit 138 comprises a demodulator and a
microprocessor. The demodulator demodulates digital signals sent
from the external control unit 136. The microprocessor of the
control unit 138 receives the digital packet, decodes it and,
provided that the power supply of the energizer unit 126 has
sufficient energy stored, sends a signal via a signal line 144
to the motor 128 to either contract or enlarge the restriction
device depending on the received command code.
Alternatively, the energy stored in the power supply of the
energizer unit may only be used for powering a switch, and the
energy for powering the motor 128 may be obtained from another
implanted power source of relatively high capacity, for example
a battery. In this case the switch is adapted to connect said
battery to the control unit 138 in an on mode when said switch
is powered by said power supply and to keep said battery
disconnected from the control unit in a standby mode when said
switch is unpowered.
With reference to FIGURE 19, the remote control
schematically described above will now be described in accordance
with a more detailed embodiment. The external control unit 136
comprises a microprocessor 146, a signal generator 148 and a
power amplifier 150 connected thereto. The microprocessor 146 is
adapted to switch the signal generator 148 on/off and to
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modulate signals generated by the signal generator 148 with
digital commands that are sent to implanted components of the
apparatus. The power amplifier 150 amplifies the signals and
sends them to the external signal transmitting antenna 132. The
5 antenna 132 is connected in parallel with a capacitor 152 to form
a resonant circuit tuned to the frequency generated by the signal
generator 148.
The implanted signal receiving antenna coil 134 forms
together with a capacitor 154 a resonant circuit that is tuned
10 to the same frequency as the transmitting antenna 132. The signal
receiving antenna coil 134 induces a current from the received
high frequency electromagnetic waves and a rectifying diode 160
rectifies the induced current, which charges a storage capacitor
158. A coil 156 connected between the antenna coil 134 and the
15 diode 160 prevents the capacitor 158 and the diode 160 from
loading the circuit of the signal receiving antenna 134 at higher
frequencies. Thus, the coil 156 makes it possible to charge the
capacitor 158 and to transmit digital information using amplitude
modulation.
20 A capacitor 162 and a resistor 164 connected in parallel and
a diode 166 forms a detector used to detect amplitude modulated
digital information. A filter circuit is formed by a resistor 168
connected in series with a resistor 170 connected in series with
a capacitor 172 connected in series with the resistor 168 via
25 ground, and a capacitor 174, one terminal of which is connected
between the resistors 168,170 and the other terminal of which is
connected between the diode 166 and the circuit formed by the
capacitor 162 and resistor 164. The filter circuit is used to
filter out undesired low and high frequencies. The detected and
30 filtered signals are fed to an implanted microprocessor 176 that
decodes the digital information and controls the motor 128 via
an H-bridge 178 comprising transistors 180,182,184 and 186. The
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motor 128 can be driven in two opposite directions by the H-
bridge 178.
The microprocessor 176 also monitors the amount of stored
energy in the storage capacitor 158. Before sending signals to
activate the motor 128, the microprocessor 176 checks whether the
energy stored in the storage capacitor 158 is enough. If the
stored energy is not enough to perform the requested operation,
the microprocessor 176 waits for the received signals to charge
the storage capacitor 158 before activating the motor 128.
