U.S. patent application number 10/253608 was filed with the patent office on 2003-04-10 for controlled food intake restriction.
This patent application is currently assigned to Obtech Medical AG. Invention is credited to Forsell, Peter.
Application Number | 20030066536 10/253608 |
Document ID | / |
Family ID | 27733664 |
Filed Date | 2003-04-10 |
United States Patent
Application |
20030066536 |
Kind Code |
A1 |
Forsell, Peter |
April 10, 2003 |
Controlled food intake restriction
Abstract
A food intake restriction apparatus and method includes and uses
an operable restriction device implanted in a patient and engaging
the stomach or esophagus to form a restricted stoma opening in the
stomach or esophagus. A source of energy for energizing the
restriction device, and a control device for releasing energy from
the source of energy from outside the patient's body are provided.
The released energy is used in connection with the operation of the
restriction device to vary the size of the stoma opening to allow
or substantially prevent the passage of food therethrough.
Inventors: |
Forsell, Peter; (Menzingen,
SE) |
Correspondence
Address: |
NIXON & VANDERHYE P.C.
8th Floor
1100 North Glebe Road
Arlington
VA
22201-4714
US
|
Assignee: |
Obtech Medical AG
|
Family ID: |
27733664 |
Appl. No.: |
10/253608 |
Filed: |
September 25, 2002 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10253608 |
Sep 25, 2002 |
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09503149 |
Feb 11, 2000 |
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6461293 |
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60148345 |
Aug 12, 1999 |
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Current U.S.
Class: |
128/899 |
Current CPC
Class: |
A61B 2017/00017
20130101; A61N 1/3787 20130101; A61F 2/004 20130101; A61F 5/0003
20130101; A61B 2090/064 20160201; A61F 2/0036 20130101; A61F
2250/0001 20130101; A61B 2017/00539 20130101; A61B 17/1355
20130101 |
Class at
Publication: |
128/899 |
International
Class: |
A61B 019/00 |
Claims
What is claimed is:
1. A food intake restriction apparatus, comprising: an operable
restriction device implanted in a patient and engaging the stomach
or esophagus to form an upper pouch of the stomach and a restricted
stoma opening in the stomach or esophagus, a source of energy for
energizing said restriction device, and a control device operable
from outside the patient's body for releasing energy from said
source of energy, said released energy being used in connection
with the operation of said restriction device.
2. The apparatus according to claim 1, wherein said control device
controls said restriction device.
3. The apparatus according to claim 2, wherein said control device
comprises an internal control unit implanted in the patient for
controlling said operation device.
4. The apparatus according to claim 3, wherein said internal
control unit is programmable.
5. The apparatus according to claim 4, wherein said control device
comprises an external control unit outside the patient's body, said
internal control unit being programmable by said external control
unit.
6. The apparatus according to claim 4, wherein said internal
control unit is programmable for controlling said restriction
device over time.
7. The apparatus according to claim 6, wherein said internal
control unit controls said restriction device over time in
accordance with an activity schedule program.
8. The apparatus according to claim 6, wherein said internal
control unit comprises a microprocessor.
9. The apparatus according to claim 5, wherein said external
control unit loads said internal control unit with data in
accordance with a loading mode only authorized for a doctor.
10. The apparatus according to claim 5, wherein said external
control unit controls said internal control unit in accordance with
a doctor mode only authorized for a doctor.
11. The apparatus according to claim 5, wherein said external
control unit controls said internal control unit in accordance with
a patient mode permitted for the patient.
12. The apparatus according to claim 1, further comprising an
operation device implanted in the patient for operating said
restriction device, wherein said control device controls said
operation device to operate said restriction device.
13. The apparatus according to claim 12, wherein said operation
device comprises hydraulic means and at least one valve for
controlling a fluid flow in said hydraulic means.
14. The apparatus according to claim 13, wherein said control
device comprises a wireless remote control for controlling said
valve.
15. The apparatus according to claim 12, wherein said restriction
device comprises hydraulic means and said operation device
comprises a reservoir forming a fluid chamber with a variable
volume connected to said hydraulic means, and said operation device
distributes fluid from said chamber to said hydraulic means by
reduction of the volume of said chamber and withdraws fluid from
said hydraulic means to said chamber by expansion of the volume of
said chamber.
16. The apparatus according to claim 12, wherein said source of
energy is external to the patient's body and said control device
releases wireless energy from said source of energy.
17. The apparatus according to claim 16, wherein said operation
device comprises a motor.
18. The apparatus according to claim 17, wherein said motor
comprises a rotary motor, and said control device controls said
rotary motor to rotate a desired number of revolutions.
19. The apparatus according to claim 17, wherein said motor
comprises a linear motor.
20. The apparatus according to claim 17, wherein said motor
comprises a hydraulic or pneumatic fluid motor, and said control
device controls said fluid motor.
21. The apparatus according to claim 17, wherein said motor
comprises an electric motor having electrically conductive parts
made of plastics.
22. The apparatus according to claim 16, wherein said control
device releases energy from said source of energy.
23. The apparatus according to claim 16, wherein said control
device shifts polarity of said released energy to reverse said
operation device.
24. The apparatus according to claim 16, wherein said operation
device comprises an electric motor and said released energy
comprises electric energy.
25. The apparatus according to claim 16, wherein said restriction
device is operable to perform a reversible function.
26. The apparatus according to claim 25, further comprising a
reversing device implanted in the patient for reversing said
function performed by said restriction device.
27. The apparatus according to claim 26, wherein said control
device controls said reversing device to reverse said function
performed by said restriction device.
28. The apparatus according to claim 26, wherein said reversing
device comprises hydraulic means including a valve for shifting the
flow direction of a fluid in said hydraulic means.
29. The apparatus according to claim 26, wherein said reversing
device comprises a mechanical reversing device.
30. The apparatus according to claim 29, wherein said mechanical
reversing device comprises a switch.
31. The apparatus according to claim 29, wherein said reversing
device comprises a gear box.
32. The apparatus according to claim 27, wherein said reversing
device comprises a switch.
33. The apparatus according to claim 32, wherein said switch is
operable by said released energy.
34. The apparatus according to claim 33, wherein said control
device controls the operation of said switch by shifting polarity
of said released energy supplied to said switch.
35. The apparatus according to claim 32, wherein said switch
comprises an electric switch and said source of energy supplies
electric energy for the operation of said switch.
36. The apparatus according to claim 32, wherein said operation
device comprises a motor, and said reversing device reverses said
motor.
37. The apparatus according to claim 16, wherein said restriction
device comprises hydraulic means and said operation device
comprises a pump for pumping a fluid in said hydraulic means.
38. The apparatus according to claim 37, wherein said operation
device comprises a motor for driving said pump.
39. The apparatus according to claim 38, wherein said operation
device comprises a fluid conduit between said pump and said
hydraulic means of said restriction device, and a reservoir for
fluid, said reservoir forming part of said conduit.
40. The apparatus according to claim 39, wherein said hydraulic
means, pump and conduit is devoid of any non-return valve.
41. The apparatus according to claim 40, wherein said reservoir
forms a fluid chamber with a variable volume, and said pump
distributes fluid from said chamber to said hydraulic means of said
restriction device by reduction of the volume of said chamber and
withdraws fluid from said hydraulic means to said chamber by
expansion of the volume of said chamber.
42. The apparatus according to claim 1, wherein said source of
energy is implanted in the patient.
43. The apparatus according to claim 42, wherein said implanted
source of energy comprises at least one 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.
44. The apparatus according to claim 43, wherein said implanted
source of energy comprises an electric source of energy.
45. The apparatus according to claim 44, wherein said electric
source of energy comprises an accumulator, or a battery having a
life-time of at least 10 years.
46. The apparatus according to claim 42, wherein said control
device controls said restriction device.
47. The apparatus according to claim 46, further comprising an
operation device implanted in the patient for operating said
restriction device, wherein said control device controls said
operation device to operate said restriction device.
48. The apparatus according to claim 47, wherein said operation
device comprises a motor.
49. The apparatus according to claim 48, wherein said motor
comprises a rotary motor, and said control device controls said
rotary motor to rotate a desired number of revolutions.
50. The apparatus according to claim 48, wherein said motor
comprises a hydraulic or pneumatic fluid motor, and said control
device controls said fluid motor.
51. The apparatus according to claim 48, wherein said motor
comprises a casing of electrically conductive plastics.
52. The apparatus according to claim 46, wherein said control
device releases energy from said implanted source of energy.
53. The apparatus according to claim 46, wherein said control
device shifts polarity of said released energy to reverse said
operation device.
54. The apparatus according to claim 46, wherein said operation
device comprises an electric motor and said released energy
comprises electric energy.
55. The apparatus according to claim 53, wherein said restriction
device comprises hydraulic means, and said operation device
comprises a pump for pumping a fluid in said hydraulic means and a
motor for driving said pump.
56. The apparatus according to claim 42, wherein said restriction
device is operable to perform a reversible function.
57. The apparatus according to claim 56, further comprising a
reversing device implanted in the patient for reversing said
function performed by said restriction device.
58. The apparatus according to claim 57, wherein said control
device controls said reversing device to reverse said function
performed by said restriction device.
59. The apparatus according to claim 57, wherein said reversing
device comprises hydraulic means including a valve for shifting the
flow direction of a fluid in said hydraulic means.
60. The apparatus according to claim 57, wherein said reversing
device comprises a mechanical reversing device.
61. The apparatus according to claim 60, wherein said mechanical
reversing device comprises a switch.
62. The apparatus according to claim 60, wherein said mechanical
reversing device comprises a gear box.
63. The apparatus according to claim 57, wherein said reversing
device comprises a switch.
64. The apparatus according to claim 63, wherein said switch is
operable by energy released from said source of energy.
65. The apparatus according to claim 63, wherein said control
device controls the operation of said switch by shifting polarity
of said released energy supplied to said switch.
66. The apparatus according to claim 63, wherein said switch
comprises an electric switch and said source of energy supplies
electric energy for the operation of said switch.
67. The apparatus according to claim 57, wherein said operation
device comprises a motor, and said reversing device reverses said
motor.
68. The apparatus according to claim 42, wherein said restriction
device comprises hydraulic means, and said operation device
comprises a pump for pumping a fluid in said hydraulic means and a
motor for driving said pump.
69. The apparatus according to claim 68, wherein said operation
device comprises a fluid conduit between said pump and said
hydraulic means of said restriction device, and a reservoir for
fluid, said reservoir forming part of said conduit.
70. The apparatus according to claim 69, wherein said hydraulic
means, pump and conduit are devoid of any non-return valve.
71. The apparatus according to claim 69, wherein said reservoir
forms a fluid chamber with a variable volume, and said pump
distributes fluid from said chamber to said hydraulic means of said
restriction device by reducing the volume of said chamber and
withdraws fluid from said hydraulic means to said chamber by
expanding the volume of said chamber.
72. The apparatus according to claim 1, further comprising at least
one implanted sensor for sensing at least one physical parameter of
the patient.
73. The apparatus according to claim 72, wherein said control
device controls said restriction device in response to signals by
said sensor.
74. The apparatus according to claim 73, wherein said control
device comprises an internal control unit implanted in the patient,
said internal control unit directly controlling said restriction
device in response to signals by said sensor.
75. The apparatus according to claim 73, wherein said control
device comprises an external control unit outside the patient's
body, said external control unit controlling said restriction
device in response to signals by said sensor.
76. The apparatus according to claim 75, wherein said external
control unit directly controls said restriction device in response
to signals by said sensor.
77. The apparatus according to claim 75, wherein said external
control unit stores information on said physical parameter sensed
by said sensor and is manually operated to control said restriction
device based on said stored information.
78. The apparatus according to claim 72, further comprising at
least one implanted sender for sending information on said physical
parameter sensed by said sensor.
79. The apparatus according to claim 1, further comprising an
external data communicator outside the patient's body and an
internal data communicator implanted in the patient for
communicating with said external communicator, wherein said
implanted communicator feeds data related to the patient back to
said external communicator or said external communicator feeds data
to said internal communicator.
80. The apparatus according to claim 79, wherein said implanted
communicator feeds data related to said implanted restriction
device.
81. The apparatus according to claim 79, wherein said implanted
communicator feeds data related to at least one physical signal of
the patient.
82. The apparatus according to claim 1, further comprising a switch
implanted in the patient for directly or indirectly switching said
energy released from said source of energy.
83. The apparatus according to claim 1, wherein said restriction
device controls the cross-sectional area of said food
passageway.
84. The apparatus according to claim 83, wherein said restriction
device is operable to open and close said food passageway.
85. The apparatus according to claim 83, wherein said restriction
device steplessly controls the cross-sectional area of said food
passageway.
86. The apparatus according to claim 1, further comprising a
pressure sensor for directly or indirectly sensing the pressure in
said food passageway.
87. The apparatus according to claim 86, wherein said control
device controls said restriction device in response to signals from
said pressure sensor.
88. The apparatus according to claim 1, further comprising an
implanted energy transfer device, wherein said control device
releases electric energy and said energy transfer device transfers
said electric energy into kinetic energy for operation of said
restriction device.
89. The apparatus according to claim 88, wherein said restriction
device is directly operated with said kinetic energy, as said
energy transfer device transfers said electric energy into kinetic
energy.
90. The apparatus according to claim 1, wherein said restriction
device is non-inflatable.
91. The apparatus according to claim 1, wherein said control device
releases energy for a determined time period.
92. The apparatus according to claim 1, wherein said control device
releases energy in a determined number of energy pulses.
93. The apparatus according to claim 1, wherein said control device
comprises a wireless remote control transmitting at least one
wireless control signal for controlling said restriction
device.
94. The apparatus according to claim 93, wherein said remote
control is capable of obtaining information on the condition of
said implanted restriction device and to control said restriction
device in response to said information.
95. The apparatus according to claim 93, wherein said wireless
remote control comprises at least one external signal transmitter
or tranceiver and at least one internal signal receiver or
transciever implanted in the patient.
96. The apparatus according to claim 93, wherein said wireless
remote control comprises at least one external signal reciever or
transceiver and at least one internal signal transmitter or
transceiver implanted in the patient.
97. The apparatus according to claim 93, wherein said remote
control is capable of sending information related to said
restriction device from inside the patient's body to the outside
thereof.
98. The apparatus according to claim 97, wherein said remote
control controls said restriction device in response to said
information.
99. The apparatus according to claim 93, wherein said remote
control transmits a carrier signal for carrying said control
signal.
100. The apparatus according to claim 99, wherein said carrier
signal is frequency, amplitude or frequency and amplitude
modulated.
101. The apparatus according to claim 99, wherein said carrier
signal is digital, analog or digital and analog.
102. The apparatus according to claim 99, wherein said control
signal used with said carrier signal is frequency, amplitude or
frequency and amplitude modulated.
103. The apparatus according to claim 93, wherein said control
signal comprises a wave signal comprising one of a sound wave
signal including an ultrasound wave signal, an electromagnetic wave
signal including an infrared light signal, a visible light signal,
an ultra violet light signal and a laser light signal, a micro wave
signal, a radio wave signal, an x-ray radiation signal, and a gamma
radiation signal.
104. The apparatus according to claim 93, wherein said control
signal comprises an electric, magnetic or electric and magnetic
field.
105. The apparatus according to claim 93, wherein said control
signal is digital, analog or digital and analog.
106. The apparatus according to claim 105, wherein said remote
control transmits an electromagnetic carrier wave signal for
carrying said digital or analog control signal.
107. The apparatus according to claim 93, wherein said control
signal is transmitted in pulses by said wireless remote
control.
108. The apparatus according to claim 88, further comprising an
implanted capacitor for stabilizing said electric energy released
by said control device.
109. The apparatus according to claim 1, wherein said control
device releases energy from said source of energy in a non-invasive
manner.
110. The apparatus according to claim 1, wherein said control
device releases magnetic energy.
111. The apparatus according to claim 1, wherein said control
device releases electromagnetic energy.
112. The apparatus according to claim 1, wherein said control
device releases kinetic energy.
113. The apparatus according to claim 1, wherein said control
device releases thermal energy.
114. The apparatus according to claim 1, wherein said control
device releases energy from said source of energy in a mechanical
manner.
115. The apparatus according to claim 1, wherein said control
device releases non-magnetic energy.
116. The apparatus according to claim 1, wherein said control
device releases non-electromagnetic energy.
117. The apparatus according to claim 1, wherein said control
device releases non-kinetic energy.
118. The apparatus according to claim 1, wherein said control
device releases or non-thermal energy.
119. The apparatus according to claim 1, wherein said control
device releases energy from said source of energy in a
non-mechanical manner.
120. The apparatus according to claim 16, further comprising an
energy storage device implanted in the patient for storing said
wireless energy released from said external source of energy.
121. The apparatus according to claim 120, wherein said energy
storage device comprises an accumulator.
122. The apparatus according to claim 121, wherein said accumulator
comprises an electric accumulator.
123. The apparatus according to claim 122, wherein said electric
accumulator comprises at least one capacitor or at least one
rechargeable battery, or a combination of at least one capacitor
and at least one rechargeable battery
124. The apparatus according to claim 16, further comprising a
battery implanted in the patient for supplying electric energy to
implanted electric energy consuming components of the
apparatus.
125. A method of treating morbid obesity comprising: implanting an
operable restriction device in a patient in engagement with the
stomach or esophagus to form an upper pouch of the stomach and a
restricted stomaopening in the stomach or esophagus, providing a
source of energy for energizing the restriction device, and
controlling the source of energy to release energyfor use in
connection with the operation of the restriction device.
126. A method according to claim 125, further comprising using
energy released from the source of energy to operate the
restriction device to enlarge and reduce, respectively, the stoma
opening.
127. A method of treating morbid obesity comprising: placing at
least two laparascopical trocars in an obese 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 in engagement with the stomach or
esophagus to form an upper pouch of the stomach and a restricted
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.
128. A method of treating morbid obesity, comprising: placing at
least two laparascopical trocars in an obese 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 in engagement with the
stomach or esophagus to form an upper pouch and a restricted stoma
opening in the stomach or esophagus, implanting an energy transfer
device in the patient, providing an external source of energy,
controlling the external source of energy to release wireless
energy, and transferring the wireless energy by the energy transfer
device into energy for use in connection with the operation of the
restriction device.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application is based upon provisional application
serial No. 60/148,345 filed Aug. 12, 1999, the disclosure of which
is hereby incorporated by reference herein.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to a food intake restriction
apparatus and method. More specifically, the invention relates to a
food intake restriction apparatus and method for surgical
application in the abdomen of a patient for forming an upper pouch
and a stoma opening in the stomach or esophagus. The term patient
includes an animal or a human being.
[0003] 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 reduced 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. Pat. No. 4,592,339, 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.
[0004] 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 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.
[0005] 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.
[0006] 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, these measures
require the use of an injection needle penetrating the skin of the
patient, which is uncomfortable for the patient.
SUMMARY OF THE INVENTION
[0007] 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.
[0008] Another object of the present invention to provide a new
food intake restriction which is easy to adjust and does not
require the use of an injection needle for accomplishing
post-operation adjustments of the stoma opening.
[0009] Accordingly, there is provided a food intake restriction
apparatus, comprising an operable restriction device implanted in a
patient and engaging the stomach or esophagus to form an upper
pouch and a restricted stoma opening in the stomach or esophagus, a
source of energy for energizing the restriction device, and a
control device operable from outside the patient's body for
releasing energy from the source of energy, wherein the released
energy is used in connection with the operation of the restriction
device.
[0010] As a result, the advantage is achieved that the implanted
restriction device can be non-invasively operated, when the
restriction device has to be 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 natural life, and at lest
many years.
[0011] The restriction device preferably controls the size of the
stoma opening. This may allow the patient to temporarily open up
the stoma opening to remove food pieces stuck therein.
[0012] The control device may also control the restriction device.
The control device may comprise an internal control unit,
preferably including a microprocessors implanted 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 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.
[0013] which may be adapted to the patient's needs.
[0014] 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 certain functions of the
restriction device controlled by the patient and other more
advanced functions controlled by the doctor resulting, which
enables a flexible post-operation treatment of the patient.
[0015] Generally, the apparatus further comprises an operation
device implanted 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 implanted energy consuming components of
the apparatus. 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 stabilizer 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 extremely
reliable.
[0016] 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.
[0017] 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.
[0018] 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 releases wireless energy from the source of energy. An
energy storage device, preferably an electric accumulator, may be
implanted 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 implanted
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
implanted control unit the electronic circuit thereof and the
restriction device may be directly powered with transformed
wireless energy, or energy from either the implanted energy storage
device or battery.
[0019] In a first particular embodiment in accordance with the
first main aspect 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 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.
[0020] In a second particular embodiment in accordance with the
first main aspect 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.
[0021] In a third particular embodiment in accordance with the
first main aspect of the invention, the restriction device is
operable to perform a reversible function and there is a reversing
device implanted in the patient for reversing the function
performed by the restriction device. Such a reversing function
preferably involves enlarging and restricting the food passageway
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 gear box.
[0022] 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.
[0023] In accordance with the third particular embodiment, the
operation device preferably comprises a motor, wherein the
reversing device reverses the motor.
[0024] In a fourth particular embodiment in accordance with the
first main aspect of the invention, the restriction device
comprises hydraulic means, for example including an
expansible/contractible cavity for fluid. The operation device
preferably comprises a pump for pumping a fluid in the hydraulic
means, a motor for driving the pump, a valveless fluid conduit
between the pump and the hydraulic means of the restriction device,
and a reservoir for fluid, wherein the reservoir forms part of the
conduit. All of the hydraulic components involved are preferably
devoid of any non-return valve. This is of great advantage, because
with valves involved there is always a risk of malfunction due to
improperly 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.
[0025] In accordance with a second main aspect of the invention,
the source of energy is implanted in the patient. Thus, the control
device releases energy from the implanted source of energy from
outside the patient's body. This solution is advantageous for
embodiments of the apparatus that have a relatively high energy
consumption which cannot be satisfied by direct supply of wireless
energy.
[0026] The source of energy thus implanted may comprise an
accumulator, preferably an electric source of energy, such as a
battery having a life-time of at least 10 years.
[0027] The above first, second, third and fourth particular
embodiments described in connection with the first main aspect of
the invention are also applicable in accordance with the second
main aspect of the invention, i.e. where the source of energy is
implanted.
[0028] All of the above embodiments may be combined with at least
one implanted 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. The expression "indirectly
sensing the pressure in the food stomach" should be understood to
encompass the cases where the sensor senses the pressure against
the restriction device or human tissue of the patient. The pressure
sensor may be any suitable known or conventional pressure sensor
such as shown in U.S. Pat. No. 5,540,731, 4,846,181, 4,738,267,
4,571,749, 4,407,296 or 3,939,823; or an NPC-102 Medical
Angioplasty Sensor. Where the control device comprises an internal
control unit 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.
[0029] Where the control device comprises an external control unit
outside the patient's body, the external control unit may, suitably
directly, control the restriction device in response to signals by
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 implanted
sender for sending information on the physical parameter sensed by
the sensor.
[0030] An external data communicator may be provided outside the
patient's body and an internal data communicator may be implanted
in the patient for communicating with the external communicator.
The implanted communicator may feed data related to the patient, or
related to the implanted restriction device, back to the external
communicator. Alternatively or in combination, the external
communicator may feed data to the internal communicator. The
implanted communicator may suitably feed data related to at least
one physical signal of the patient.
[0031] Generally, the apparatus of the invention may comprise a
switch implanted in the patient for directly or indirectly
switching the energy released from the source of energy. The
restriction device may control the size of the stoma opening in the
stomach or esophagus. For example, the restriction device may be
operable to open and close the stoma opening or may steplessly
control the latter. A pressure sensor may be provided for directly
or indirectly sensing the pressure in the stomach. The control
device may control the restriction device in response to signals
from the pressure sensor.
[0032] 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.
[0033] The apparatus may comprise an implanted energy transfer
device, wherein the control device releases electric energy and the
energy transfer device transfers the electric energy into kinetic
energy for, preferably direct, operation of the restriction device.
Suitably, an implanted stabilizer, such as a capacitor or a
rechargeable accumulator, or the like, may be provided for
stabilizing the electric energy released by the control device. In
addition, the control device may release energy for a determined
time period or in a determined number of energy pulses. 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 over a period of time, which is beneficial with respect to the
treatment of the patient
[0034] The wireless remote control may be capable of obtaining
information on the condition of the implanted 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.
[0035] 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 implanted in the patient. In another particular
embodiment of the invention, the wireless remote control comprises
at least one external signal receiver or transceiver and at least
one internal signal transmitter or transceiver implanted in the
patient.
[0036] 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.
[0037] 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 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.
[0038] The control signal may be digital or analog, and may
comprise an electric or magnetic field. Suitably, the wireless
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.
[0039] In all of the above solutions, the control device
advantageously releases energy from the source of energy in a
non-invasive, mechanical or non-mechanical manner.
[0040] The control device may release magnetic, electromagnetic,
kinetic or thermal energy, or non-magnetic, non-thermal,
non-electromagnetic or non-kinetic energy.
[0041] Another object of the present invention is to provide
methods for treating morbid obesity.
[0042] Accordingly, in accordance with a first alternative there is
provided a method of treating morbid obesity, comprising the steps
of implanting an operable restriction device in a patientin
engagement with the stomach or the esophagus to form a restricted
stoma 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 of energy to operate the
restrictiondevice to enlarge and reduce, respectively, the food
pasageway.
[0043] In accordance with a second alternative there is provided a
method of treating morbid obesity, comprising the steps of placing
at least two laparascopical trocars in a 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 the esophagus to form a restricted stoma in the stomach or
esophagus, implanting a source of energy in the patient, and
controlling the implanted source of energy from outside the
patients body to release energy for use in connection with the
operation of the restriction device.
[0044] In accordance with a third alternative there is provided a
method of treating morbid obesity, comprising the steps of placing
at least two laparascopical trocars in a 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 in engagement with the stomach or esophagus to
form a restricted stoma in the stomach or esophagus, implanting an
energy transfer device in the patient, providing an external source
of energy, controlling the external source of energy to release
wireless energy, and transferring the wireless energy by the energy
transfer device into energy suited for use in connection with the
operation of the restriction device.
BRIEF DESCRIPTION OF THE DRAWINGS
[0045] FIGS. 1 to 4 are schematic block diagrams illustrating four
embodiments, respectively, of the invention, in which wireless
energyis released from an external source of energy;
[0046] FIGS. 5 to 8 are schematic block diagrams illustrating four
embodiments, respectively, of the invention, in which energy is
released from an implanted source of energy;
[0047] FIG. 9 is a schematic block diagram illustrating conceivable
combinations of implanted components for achieving various
communication options;
[0048] FIG. 10 illustrates the apparatus in accordance with the
invention implanted in a patient;
[0049] FIG. 11 is a block diagram illustrating remote control
components of an embodiment of the invention; and
[0050] FIG. 12 is a schematic view of exemplary circuitry used for
the components of the block diagram of FIG. 11.
[0051] Referring to the drawing figures, like reference numerals
designate identical or corresponding elements throughout the
several figures.
DETAILED DESCRIPTION OF THE DRAWINGS
[0052] FIG. 1 schematically shows an embodiment of the food intake
restriction apparatus of the invention having some parts implanted
in a patient and other parts located outside the patient's body.
Thus, in FIG. 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.
[0053] The apparatus of FIG. 1 comprises an implanted operable
restriction device 4, which engages the patient's stomach or
esophagus to form an upper pouch and a restricted stoma opening in
the stomach. The restriction device 4 is capable of performing a
reversible function, i.e. to enlarge and reduce the size of 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 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. The
implanted control unit also uses energy from the control signal for
operating the restriction device 4 via a power supply line 12.
[0054] FIG. 2 shows an embodiment of the invention identical to
that of FIG. 1, except that a reversing device in the form of a
switch 14 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, i.e.
enlarging and restricting the stoma opening. More precisely, the
external control unit 10 releases energy carried by a wireless
signal and the implanted control unit 6 transfers 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.
[0055] FIG. 3 shows an embodiment of the invention identical to
that of FIG. 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
reduce the size of 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 size of the stoma opening. The external
control unit 10 releases energy carried by a wireless signal and
the implanted control unit 6 transfers 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.
[0056] FIG. 4 shows an embodiment of the invention identical to
that of FIG. 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.
[0057] FIG. 5 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.
[0058] In response to a control signal from the external control
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 reduce the
size of 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 size of the
stoma opening.
[0059] FIG. 6 shows an embodiment of the invention identical to
that of FIG. 4, except that a battery 42 is substituted for the
accumulator 28, the external control unit 40 of the embodiment of
FIG. 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.
[0060] FIG. 7 shows an embodiment of the invention identical to
that of FIG. 6, except that the motor/pump unit 36 of the
embodiment of FIG. 5 is substituted for the motor 44 and a fluid
reservoir 46 also implanted in the patient and via fluid conduits
48 and 50 connected to the motor/pump unit 36 and the 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.
[0061] FIG. 8 shows an embodiment of the invention identical to
that of FIG. 6, except that a mechanical reversing device in the
form of a gear box 52 also is implanted in the patient. The
implanted control unit 6 controls the gear box 52 to reverse the
function performed by the restriction device 4 (mechanically
operated), i.e. enlarging and restricting the food passageway.
[0062] FIG. 9 schematically shows conceivable combinations of
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, whereby the control
unit 6 controls the implanted restriction device 4 in response to
the control signal.
[0063] 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 tranceiver 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.
[0064] 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 tranceiver for
sending information on the charge condition of the battery.
[0065] Those skilled in the art will realize that the above various
embodiments according to FIGS. 1-9 could be combined in many
different ways. For example, the energy operated switch 14 could be
incorporated in any of the embodiments of FIGS. 3,4,6-8, the
hydraulic shifting device 38 could be incorporated in any of the
embodiments of FIGS. 3 and 7, and the gear box 52 could be
incorporated in any of the embodiments of FIGS. 1,4 and 6.
[0066] FIG. 10 illustrates how any of the above-described
embodiments of the food intake restriction apparatus of the
invention may be implanted in a patient. Thus,an assembly of the
apparatusimplanted in the patient comprises a restriction device 56
engaging the stomach 58,, and an operation device 60 for operating
the restriction device 56.. The restriction device 56 engages the
stomach 58 and a portion of the stomach, thereby forming an upper
pouch 61 of the stomach. And an internal control unit 62, which
includes a signal receiver, for controlling the operation device
60. An external control unit 64 includes a signal transmitter for
transmitting a control signal to the signal receiver of the
implanted control unit 62. The implanted control unit 62 is capable
of transferring signal energy from the control signal into electric
energy-or powering the operation device 60 and for energizing
energy consuming implanted components of the apparatus.
[0067] FIG. 11 shows the basic parts of a wireless remote control
of the apparatus of the invention including an electric motor 128
for operating a restriction device, for example of the type
illustrated in FIG. 10. 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 FIG. 11, 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.
[0068] 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 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.
[0069] 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.
1 Start pattern, 8 Command, 8 Count, 8 bits Checksum, 8 bits bits
bits
[0070] 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 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.
[0071] 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.
[0072] 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.
[0073] 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.
[0074] With reference to FIG. 12, 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 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 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.
[0075] The implanted signal receiving antenna coil 134 forms
together with a capacitor 154 a resonant circuit that is tuned 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
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.
[0076] 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 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 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 motor 128 can be
driven in two opposite directions by the H-bridge 178.
[0077] 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.
* * * * *