Device for non-invasive measurement of fluid pressure in an adjustable restriction device

Contents of disclosure

[Technical field] The present invention relates broadly to implantable limiting devices, and more specifically to fluid-filled limiting devices. The present invention is also related to a dietary intake limiting device for the treatment of morbid obesity.

[Background technology] Obesity is an growing concern, especially in the United States, as the obese population continues to grow and more is known about the negative effects of obesity on health. Pathological obesity is a condition in which a person weighs more than 45.4 kg (100 lbs) above his ideal body weight and poses a significant risk of serious health problems, in particular. Therefore, treating obese patients has received a great deal of attention. One way to treat morbid obesity is to place a restriction device, such as a long band, around the upper part of the stomach. The band is placed above the band to form a small gastric sac and a reduced fistula opening in the stomach. The effect of the band is to reduce the amount of food that can be eaten before becoming "full" by reducing the volume of stomach that can be used. The gastric band has typically consisted of a fluid-filled elastic balloon with a fixed end surrounding the stomach just below the esophageal and gastric junction. When the fluid is injected into the balloon, the band expands towards the stomach, creating a restricted dietary intake or fistula in the stomach. To reduce this limitation, the fluid is removed from the band.

The dietary restriction device is also composed of a mechanically regulated band, which also surrounds the upper part of the stomach. The bands include any number of elastic materials or conduction devices and drive members for adjusting the bands. In addition, gastric bands have been developed that include both hydraulic and mechanical drives. An example of such an adjustable gastric band is disclosed in US Pat. No. 6,067,991, "Mechanical Food Intake Restriction Device," issued March 30, 2000. The US patent is incorporated herein by reference. It is also known to implant an inflatable elastic balloon within the gastric cavity itself to limit the volume available for feeding in the gastric cavity itself. The balloon is filled with fluid to expand towards the stomach wall, thereby reducing the volume available for feeding in the stomach.

With each of the above dietary restriction devices, for safe and effective treatment, the devices need to be regularly monitored and adjusted to vary the degree of restriction placed on the stomach. In band instruments, the gastric sac above the band increases significantly in size after initial implantation. Therefore, the gastric fistula opening must initially be large enough to allow the patient to properly nourish while the stomach fits into the band device. As the gastric sac increases in size, the band is adjusted to change the size of the fistula. In addition, it is desirable to resize the fistula to accept changes in the patient's body or treatment regimen, or, in more urgent cases, to alleviate obstruction or severe esophageal dilation. Traditionally, the regulation of a hydraulic gastric band is performed by a clinician on a regular visit, during which a hypodermic needle and syringe are used to allow fluid to penetrate the patient's skin and add fluid to the balloon. Or it needed to be removed from the balloon. More recently, implantable pumps have been developed that allow non-invasive regulation. An external programmer controls the pump by communicating with the implanted pump using telemetry. During regular visits, the doctor places the programmer's handheld portion near the implanted device in the stomach to transmit power and command signals to the implanted device. The implanted device then adjusts the amount of fluid in the band and transmits a response instruction to the programmer.

While adjusting these gastric bands, it was difficult to determine how the adjustment was proceeding and whether the adjustment was producing the intended effect. In an attempt to determine the efficacy of the regulation, some doctors have used fluoroscopy by swallowing barium while the adjustment is taking place. However, fluoroscopy is not desirable because it is expensive and exposes both the doctor and the patient to radiation. Other doctors have instructed patients to drink a glass of water during and after regulation to determine if water passes through a regulated fistula. However, this method only reveals whether the patient is obstructed and does not provide any information about the efficacy of the regulation. In many cases, doctors simply adopt a "try as you go" method based on their previous experience, and the outcome of the adjustment is hours or days later, or the patient's stomach. It is not revealed until it experiences a complete obstruction of the cavity or until the band causes an ulcer of gastric tissue.

Therefore, it is desired to provide an effective method for assessing the regulation of dietary intake regulators during or immediately after regulation. In particular, it is desirable to provide a gastric limiting device that includes a pressure measuring system for measuring the pressure in the limiting device and therefore the size of the fistula. In addition, it is desirable to provide a non-invasive method for measuring fluid pressure during adjustment and communicating pressure measurements with an external monitor.

[Disclosure of Invention] Based on the present invention, a restriction system, such as an adjustable gastric band, for forming a restriction within the patient's body and non-invasively communicating pressure data about the restriction with an external monitor. Provided. The system includes a restriction device that is implanted in the patient's body to form a restriction. The system further includes an implanted port coupled to a restriction device. The port houses the working fluid to affect the dimensions of the limit. The system further includes a pressure sensing system that communicates with the working fluid to measure the pressure of the working fluid and transmit the pressure measurements to an external monitor.

[Detailed description of the invention] Now, with reference to the drawings in detail, similar symbols in the drawings indicate similar elements throughout the drawings, with FIG. 1 showing the dietary intake restriction system 30. System 30 is the first part implanted inside the body of patient 34 and shown as overall code 32, and the second part located outside the patient's body as overall code 36. Includes parts. The implanted first portion 32 contains an adjustable gastric band 38 located in the upper portion of the patient's stomach 40. The adjustable stomach band 38 contains a cavity made of silicone rubber or other type of biocompatible material, the cavity expanding inward with respect to the stomach 40 when filled with fluid. .. Alternatively, the gastric band 38 may include a mechanically adjustable device with a fluid cavity that is subject to changes in pressure during band adjustment, or a combination of fluid pressure / mechanical adjustments. It may be a band. An injection port 42, described in more detail below, is implanted in an area of the body accessible for needle injection and / or telemetry communication signals. In the illustrated embodiment, the infusion port 42 fluidizes through an adjustable band 38 via a catheter 44. The surgeon may also place and permanently implant an injection port 42 within the patient's body to perform dietary intake restriction, or fistula regulation. Those skilled in the art have found that surgical methods for placing gastric bands, such as the implantable first part 32, have made great strides in recent years so that patients can obtain optimal therapeutic effects with minimal complications. You will notice. The surgeon, for example, typically implants an infusion port 42 in the area below the outer ribs of the abdomen, below the patient's layers of skin and adipose tissue. The surgeon may implant the infusion port 42 into the patient's sternum.

FIG. 2 shows in more detail an exemplary adjustable gastric band. In this embodiment, the gastric band 38 has a variable volume cavity 46 that expands or contracts with respect to the outer wall of the stomach to form an adjustable fistula to controlally limit food intake to the stomach. Includes. Physicians reduce the size of the fistula opening by adding fluid to the variable volume cavity 46, or instead increase the size of the fistula by drawing fluid out of the cavity. Fluid is added or drawn by inserting a needle into the injection port 42. Alternatively, the fluid may be transferred in a non-invasive manner between the gastric band 38 and the infusion port 42 using telemetry command signals. The fluid may be 0.9 percent saline, but not limited to:

FIG. 3 shows the adjustable gastric band 38 of FIG. 2 applied around the patient's gastroesophageal junction. As shown in FIG. 3, the gastric band 38 at least substantially surrounds the upper portion of the stomach 40 near the junction with the esophagus 48. FIG. 4 is a cross-sectional view of the stomach band 38 showing the gastric band in the withered state. In this figure, the stomach band 38 contains very little or no fluid, thus maximizing the size of the fistula opening to the stomach 40. FIG. 5 is a cross-sectional view of a stomach band 38 and a stomach 40 similar to FIG. 4 showing a swollen, fluid-filled shape of the stomach band 38. In this figure, the pressure of the stomach band 38 against the stomach 40 increases due to the fluid in the band, thereby reducing the fistula opening to create a restriction on food intake. FIG. 5 also shows dilation of the esophagus 48 above the gastric band 38, which forms the upper sac 50 below the diaphragm muscle 52.

Now referring again to FIG. 1, the external portion 36 of the food intake restriction system 30 is electrically connected to the control box 64 (in this embodiment, by the electrical cable assembly 12) the pressure reader 60. Includes. The control box 64 includes a display 66, one or more control switches 68, and an external control module, which are described in more detail below. The control box 64 may be configured for use, for example, in a doctor's office or laboratory. Several ways to attach the control box 64 include placing it on a table, attaching it to an inspection table, or hanging it on a portable stand. The control box 64 may be configured to be carried in the pocket of a physician's laboratory garment, held by hand, or placed on a laboratory table or a lying patient. .. The electrical cable assembly 62 may be detachably coupled to a control box 64 or pressure reading device 60 for ease of cleaning, maintenance, use, and storage of the external portion 36 of the system 30. The pressure reader 60 non-invasively measures the pressure of the fluid within the implanted portion 32, even when the injection port 42 is implanted under thick (at least 10 cm or more) subcutaneous adipose tissue. To do. The physician may hold the pressure reading device 60 against the patient's skin near the location of the injection port 42 in the patient's body and observe the pressure reading on the display 66 of the control box 64. The pressure reading device 60 may be detachably attached to the patient by straps, adhesives, or other known methods, such as during long-term examinations. The pressure reading device 60 operates through a conventional cloth or paper surgical drape and may include a disposable cover (not shown) that is replaced on a patient-by-patient basis.

Now referring to FIG. 6, FIG. 6 shows a partial cross-sectional side view of the injection port 42 containing a pressure sensing system for non-invasively measuring the pressure of the fluid in the implanted portion 32. ing. As shown in FIG. 6, the injection port 42 includes a rigid housing 70 having an annular flange 72 with multiple mounting openings 74 for fastening the injection port 42 to the patient's tissue. The surgeon may attach the injection port to tissue such as the fascia that covers the abdominal muscles using any of a variety of surgical fasteners such as suture filaments, staples, and clips. The injection port 42 further includes a bulkhead 76 that is typically made of silicone rubber and is compressed and maintained within the housing 70. The septum 76 is punctured by a Huber needle or an injection device of the same type to add fluid to or draw fluid from the injection port 42. The septum 76 automatically seals when the needle is pulled out to maintain the volume of fluid in the injection port 42. The infusion port 42 further includes a reservoir 80 for maintaining the working fluid and a catheter connector 82. The connector 82 is attached to the catheter 44 shown in FIG. 2 to form a closed fluid circuit between the reservoir 80 inside the infusion port 42 and the cavity 46 in the adjustable band 38. There is. The fluid from the reservoir 80 is used to expand the volume of the band cavity 46. Instead, the fluid may be removed from the cavity 46 and retained in the reservoir 80 to temporarily reduce the volume of the cavity 46. The housing 70 and connector 82 may be integrally molded from a biocompatible polymer or may be composed of a metal such as titanium or stainless steel.

A pressure sensing system is provided at the injection port 42 to measure the pressure of the fluid in the closed fluid circuit of the implanted portion 32. The pressure in the fluid circuit corresponds to the amount of limitation applied to the patient's stomach by the adjustable band. Therefore, by measuring the pressure of the fluid, the physician can assess the limits created by band adjustment. Fluid pressure may be measured before, during, and / or after adjustment to verify that the band is properly adjusted. In the embodiment shown in FIG. 6, the pressure sensing system includes a sensor 84 located at the bottom of the fluid reservoir 80 within the housing 70. A maintenance cover 86 extends over the pressure sensor 84, substantially separating the surface of the sensor from the reservoir 80 and protecting the sensor from needle puncture. The maintenance cover 86 may be made of a ceramic material such as alumina, which can prevent electronic communication between the pressure sensor 84 and the pressure reader 60 while preventing needle puncture. Absent. The maintenance cover 86 includes ventilation holes 90 that allow the fluid in the reservoir 80 to flow toward the surface of the pressure sensor 84 and give a strong impact to the surface of the pressure sensor 84.

FIG. 7 is an isometric view of the maintenance cover 86 showing the ventilation holes 90 on the bottom surface of the maintenance cover 86. FIG. 8 is an isometric view showing the outside of the pressure sensor 84. As shown in FIG. 8, the exterior of the pressure sensor 84 contains a strain element with a deformable surface. In the illustrated embodiment, the strain element is the diaphragm 92. The diaphragm 92 may be formed by thinning a portion of the wall of the titanium reservoir 80. The diaphragm 92 may be made of titanium or other similar material and has a thickness of 0.00254 cm (0.001 inch) to 0.00508 cm (0.002 inch). Although this embodiment shows the diaphragm as a strain element, the present invention may be configured and implemented with another strain element that converts the pressure of the fluid into a mechanical displacement. Examples of other suitable strain elements include, but are not limited to, Bourdon tubes and bellows assemblies. The pressure sensor 84 is hermetically sealed within the housing 94 to prevent fluid from entering and operating the sensor. The housing 94 is sealed to the housing 70 of the injection port 42 to prevent fluid from being lost from the injection port 42. The diaphragm 92 is hermetically sealed in the sensor housing 94 to prevent fluid from flowing out along the edges of the diaphragm and into the internal components of the detection system. As the fluid passes through the ventilation holes 90 of the reservoir 80, the fluid exerts a strong impact on the surface of the diaphragm 92. As the fluid passes through the ventilation holes 90, the diaphragm 92 responds to changes in the pressure of the fluid in the fluid circuit and converts the changes in pressure into mechanical displacements.

FIG. 9 is a side sectional view of the pressure sensor 84 along line AA of FIG. 8 showing a first embodiment 88 for measuring the pressure of a fluid. In the embodiment shown in FIG. 9, the mechanical displacement of the diaphragm 92 is converted into an electrical signal by a pair of variable resistance silicon strain gauges 96,98. Strain gauges 96,98 are attached to the diaphragm 92 on the opposite side of the working fluid in the reservoir 80. The strain gauge 96 is attached to the central portion of the diaphragm 92 to measure the displacement of the diaphragm. A second, paired strain gauge 98 is mounted near the outer edge of the diaphragm 92. The strain gauges 96,98 may be attached to the diaphragm 92 by an adhesive or may be diffused within the structure of the diaphragm. As the pressure of the fluid in the band 38 changes, the surface of the diaphragm 92 deforms up or down within the surface of the housing 94. Such deformation of the diaphragm 92 produces a change in resistance at the central strain gauge 96.

As shown in FIG. 10, strain gauges 96,98 form two resistors on a semi-compensated Wheatstone bridge circuit 100. When the strain gauge 96 responds to the mechanical deformation of the diaphragm 92, changes in the resistance of the strain gauge change the potential difference over the upper part of the bridge circuit. The strain gauge 98 is paired with the strain gauge 98 to insulate the Wheatstone bridge circuit. The differential amplifiers 102 and 104 are connected to the bridge circuit 100 in order to measure the change in the potential difference of the bridge circuit by the variable resistance strain gauge. More specifically, the differential amplifier 102 measures the voltage over the entire bridge circuit, and the differential amplifier 104 measures the voltage difference over half the strain gauge of the bridge circuit 100. The larger the difference in the voltage of the strain gauge with respect to the constant voltage over the entire bridge, the larger the pressure difference. If desired, a fully compensated Wheatstone bridge circuit may be used to increase the sensitivity and accuracy of the pressure sensing system. In a fully compensated Wheatstone bridge, four strain gauges are mounted on the surface of the diaphragm 92 instead of just two strain gauges as shown in FIG.

The output signals from the differential amplifiers 102 and 104 are supplied to the microcontroller 106. The microcontroller 106 is integrated in the circuit board 110 in the housing 94. The temperature sensor 112 measures the temperature inside the implanted port and supplies a temperature signal to the microcontroller 106. The microcontroller 106 uses the temperature signal from the sensor 112 to compensate for changes in body temperature and residual temperature errors that are not counted by the strain gauge 98. Compensating the pressure measurement signal for changes in body temperature enhances the accuracy of the pressure detection system. In addition, a TET / telemetry coil 114 is located within the housing 94. The coil 114 is connected to the capacitor 116 and forms a tuned tank circuit for receiving power from the external portion 36 and transmitting the pressure measurement to the pressure reader 60.

FIG. 11 is a side sectional view similar to FIG. 9 showing a second embodiment 118 of the pressure detection system of the present invention. In a second embodiment 118, a MEMS sensor 120 is provided in the housing 94 to measure the mechanical deformation of the diaphragm 92 and generate an electrical signal proportional to the pressure in the adjustable band 38. There is. A sealed silicone oil chamber 122 is provided between the diaphragm 92 and the MEMS sensor 120. The chamber 122 protects the MEMS sensor 120 and transmits the mechanical displacement of the diaphragm 92 to the sensor 120. The MEMS sensor 120 supplies the microcontroller 106 with an electrical signal that represents the pressure of the fluid in the reservoir 80. The microcontroller 106 inputs the signal from the MEMS sensor 120 and the temperature signal from the temperature sensor 112, and calculates the measured value of the pressure. Pressure measurements are transmitted to the pressure reader 60 within the external portion 36 using telemetry signals, as described in more detail below.

FIG. 12 is a block diagram of the pressure measuring system of the first and second embodiments 88,118 of the present invention. As shown in FIG. 12, the control module 126 outside the system includes a primary TET coil 130 for transmitting power signals to the internal control module indicated by reference numeral 132 as a whole. The primary TET coil 130 is located within the pressure reading device 60 shown in FIG. The TET drive circuit 134 controls the supply of power signals to the primary TET coil 130. The TET drive circuit 134 is controlled by a microprocessor 136 with associated memory 138. A graphic user interface 140 is connected to the microprocessor 136 to control the data displayed on the display 66. The external control module 126 provides a primary telemetry transceiver 142 for transmitting query commands to the implanted control module 132 and receiving response data including fluid pressure readings from the implanted control module 132. Also includes. The primary transceiver 142 is electrically connected to the microprocessor 136 for inputting and receiving instruction and data signals. The primary transceiver 142 resonates at the selected RF communication frequency and produces a downlink alternating magnetic field 146 that transmits instruction data to the implanted control module 132. The power supply 150 supplies energy to the external control module 126 to power the system 30. The ambient pressure sensor 152 is connected to the microprocessor 136. The microprocessor 136 reads the signal from the ambient pressure sensor 152 in order to improve the accuracy of the pressure measurement value, for example, in response to a change in atmospheric pressure caused by a pressure condition or a change in altitude. Used to adjust.

FIG. 12 also shows an internal control module 132 implanted under the patient's skin 154. The internal control module 132 is located within the housing 94 of the injection port 42. As shown in FIG. 12, the secondary TET / telemetry coil 156 in the internal control module 132 receives power and command signals from the external control module 126. Coil 156 forms an inductively coupled tuned tank circuit to the primary TET coil 130 to power the implanted device or to the primary telemetry coil 144 to receive and transmit data. are doing. Telemetry transceiver 158 controls the exchange of data with coil 156. In addition, the internal control module 132 amplifies signals from the rectifier / power regulator 160, the microcontroller 106 described above, the memory 162 associated with the microcontroller, the temperature sensor 112, the pressure sensor 84, and the pressure sensor. Includes the signal processing circuit 164. The internal control module 132 transmits the temperature-controlled pressure measurement value from the pressure sensor 84 to the external control module 126. In the external control module 126, the received pressure measurement is adjusted to the change in ambient pressure and displayed on the display 66.

FIG. 13 is a side sectional view showing a third embodiment 170 for measuring the pressure of a fluid according to the present invention. In a third embodiment 170, the internal control module 132 is powered by an internal power source, such as a battery 172. The battery 172 replaces the primary and secondary TET coils 130,156 for powering the microcontroller 106 and other internal components. In this embodiment, the pressure sensing system has a pair of strain gauges 96, as in the first embodiment, to measure the mechanical deformation of the diaphragm 92 corresponding to the change in pressure within the band 38. Contains 98. Strain gauges 96,98 are incorporated within a balanced, thermally compensated bridge circuit for measuring pressure differences within the closed fluid circuit of the implanted device.

FIG. 14 is a block diagram of the pressure measuring system of the present invention based on the third embodiment 170 shown in FIG. In embodiment 170, an internal power source is used to power the internal control module 176, rather than the TET power system as in the first embodiment. The power source for the implanted portion 32 is the battery 172 rather than the TET primary coil 130 and secondary coil 156 shown in FIG. In the embodiment shown in FIG. 14, the secondary implanted coil 156 is used only for data communication between internal and external control modules. The power regulator 174 is provided to control the power from the battery 172 in order to save the battery and extend the life of the battery.

FIG. 15 shows a fourth embodiment 180 for measuring the pressure of the fluid in the adjustable band 38, where the passive system is used to measure the change in the pressure of the working fluid. In this fourth embodiment 180, a variable capacitance 182 is attached to the diaphragm 92 to measure the mechanical deformation of the diaphragm. The variable capacitance 182 includes a first electrode plate 184 attached near the center of the diaphragm 92 on the opposite side of the fluid reservoir 80. The variable capacitance second electrode plate 186 is fixed in place in the housing 94 by a capacitor mount 188. Each of the electrode plates 184, 186 is connected to the induction coil 190 to form a resonant circuit, as indicated by wire 192. When the pressure of the fluid in the reservoir 80 increases or decreases, for example due to a change in the peristaltic pressure with respect to the band 38, the position of the electrode plate 184 changes with the deformation of the diaphragm 92. As the pressure of the fluid increases, the diaphragm 92 pushes the first electrode plate 184 closer to the second electrode plate 186, thereby increasing the capacitance and lowering the resonance frequency. Similarly, when the pressure of the fluid drops in a closed fluid circuit, the first electrode plate 184, along with the diaphragm 92, moves away from the second electrode plate 186, thereby causing capacitance in the resonant circuit. To increase the resonance frequency.

FIG. 16 shows a fifth embodiment 196 for measuring the pressure of a fluid according to the present invention. Fifth embodiment 196 is another embodiment of a passive pressure sensing system in which the variable inductance coil 200 converts the mechanical deformation of the diaphragm 92 into a pressure measurement signal. As shown in FIG. 16, the inductance coil 200 is a flat coil disposed beneath the diaphragm 92, away from the diaphragm 92. A fixed capacitance 202 is connected to the inductance coil 200, as indicated by wire 204, to form an LC resonant circuit 206. As the diaphragm 92 deforms up or down in response to changes in the pressure of the working fluid, the inductance of the coil 200 changes. As the pressure of the fluid increases, the diaphragm 92 deforms towards the coil 200, thereby reducing the inductance of the coil 200 due to the coupling of vortex currents between the metal diaphragm and the coil. Conversely, as the pressure of the fluid decreases, the diaphragm 92 deforms away from the coil 200, thereby reducing the coupling of vortex currents and increasing the inductance of the coil. Therefore, the inductance of the coil 200 is inversely proportional to the pressure of the working fluid. When the inductance of the coil 200 changes, the resonance frequency of the LC resonance circuit 206 changes.

FIG. 17 is a block diagram of the pressure measurement system of the fourth and fifth embodiments 180,196 of the present invention. In this system, the microprocessor 136 controls the induction coil circuit 208 and the induction coil 210. The microprocessor 136 changes the frequency of the induction coil 210 and magnetically couples with the LC circuit 206 in the implanted portion 32, as indicated by the wire 212. The frequency at which the internal and external coils are coupled varies with the resonant frequency of the implanted LC circuit 206. The resonant frequency of the implanted LC circuit 206 changes with the pressure of the fluid in band 38. The change in resonance frequency is measured by the microprocessor 136 via the induction coil circuit 208. Once detected, the resonant frequency is compared to the known pressure at the specified frequency to determine the pressure of the fluid in band 38. The graphic user interface 140 in the external module 214 shows the measured fluid pressure on the display 66.

FIG. 18 is a graph of the pressure signal 216 from the pressure sensing system of the present invention as it appears on the display 66 during a user inquiry. In the example shown in FIG. 18, the fluid pressure is first measured by the pressure reading device 60 while the patient is at rest, and a resting pressure reading is obtained, as shown. Band 38 is then adjusted to reduce the size of the fistula. During band adjustment, the pressure sensing system continues to measure the pressure of the fluid and continues to transmit the pressure readings through the patient's skin to the pressure reader 60. As can be seen from the graph in FIG. 18, the pressure reading increases slightly after band adjustment. In the illustrated example, the patient is then asked to drink the liquid to ensure the accuracy of the regulation. When the patient drinks the liquid, the pressure detection system continues to measure the pressure spike waveform due to the peristaltic pressure swallowing the liquid and transmits the pressure reading to an external module 36 for display. By measuring and visually displaying the load of the limiting device on gastric peristalsis both during and after regulation, the present invention provides physicians with accurate and real-time visualization of the patient's response to regulation. provide. Such an immediate and lively display of recorded pressure data allows the physician to adjust the band more accurately. The data may be displayed over a period of time to provide pressure over time.

In addition to being used during regulation, the pressure sensing system of the present invention may be used to measure changes in pressure within a limiting device during different periods of treatment. Regular pressure readings allow the pressure detection system to act as a diagnostic tool to ensure that dietary intake limiting devices are functioning effectively. More specifically, a pressure sensing system may be used to detect the absence of pressure in a band indicating fluid leakage. Instead, a pressure detection system may be used to detect kinks in catheter 44 or excessive spike waveforms of pressure within the band indicating fistula obstruction.

The pressure sensing system of the present invention also allows the patient to observe his or her own treatment at home using an external monitor, such as an external device 36. Using an external device, the patient can routinely download pressure readings to his or her physician's clinic, thereby the number of clinic visits required to monitor the patient's treatment. Can be reduced. In addition, the patient should perform a pressure reading at home to inform his or her physician when the band's pressure drops below a certain baseline, indicating that a limiting device needs to be adjusted. Can be. Therefore, the pressure sensing system of the present invention has advantages as both a diagnostic and monitoring tool while treating a patient with an obesity device.

It will be readily apparent to those skilled in the art that the above invention can be similarly applied to other types of implantable bands. For example, bands are also used to treat fecal incontinence. One such band is described in US Pat. No. 6,461,292, which is incorporated herein by reference. Bands are also used to treat urinary incontinence. One such band is described in US Patent Application No. 2003/0105385, which is incorporated herein by reference. Bands are also used to treat heartburn and / or acid reflux. One such band is described in US Pat. No. 6,470,892, which is incorporated herein by reference. Bands are also used to treat impotence. One such band is described in US Patent Application No. 2003/0114729, which is incorporated herein by reference.

Although the present invention has been illustrated by describing some embodiments, it is not the applicant's intent to limit or limit the essence and scope of the claims in such detail. Various other modifications, modifications, and substitutions will be conceived by those skilled in the art without departing from the scope of the present invention. That is, the instruments and methods of the present invention have been exemplified in connection with providing a pressure sensor in the injection port. Instead, the sensor may be placed in a fluid-filled portion of the band to measure changes in pressure within the band. In addition, the pressure sensor may be associated with an elastic balloon implanted in the gastric cavity to measure the pressure of the fluid in the balloon. The structure of each element associated with the present invention may instead be described as a means for providing the functionality performed by that element. It will be understood that the above description is provided as an example, and that other modifications will be conceived by those skilled in the art without departing from the essence and scope of the claims. Let's do it.

[Implementation mode] Specific embodiments of the present invention are as follows. (1) In a restriction system for forming a restriction in the patient's body and non-invasively communicating pressure data related to the restriction with an external monitor. A restriction device for implanting in the patient's body to form a restriction in the body, b. Implanted ports coupled to the restriction device, wherein the ports contain working fluids that affect the dimensions of the restriction. c. A pressure detection system communicating with the working fluid for measuring the pressure of the working fluid and transmitting the pressure measurement data to the external monitor. A restriction system. (2) In the restriction system described in the embodiment (1). The pressure of the working fluid is proportional to the degree of restriction formed, Restriction system. (3) In the restriction system described in the embodiment (2). The pressure sensing system comprises a mechanically deformable surface in contact with the working fluid. The surface deforms in proportion to the pressure of the working fluid. Restriction system. (4) In the restriction system described in the embodiment (3). The mechanically deformable surface has a mechanical deformation on the surface, and the mechanical deformation is converted into an electrical signal representing the pressure in the working fluid. Restriction system. (5) In the restriction system described in the embodiment (4). The pressure sensing system comprises two or more variable resistance elements mounted on the deformable surface. The resistance value of the element changes in response to the mechanical deformation of the surface. The resistance element is connected to an electric circuit and The output of the electrical circuit provides a measure of the pressure of the working fluid. Restriction system. (6) In the restriction system described in the embodiment (1). The limiting device is an adjustable gastric band, Restriction system. (7) In the restriction system described in the embodiment (4). The pressure sensing system includes a variable capacitance capacitor. The capacitance of the capacitor changes in response to changes in the pressure of the working fluid, The change in capacitance provides a measure of the pressure of the working fluid. Restriction system. (8) In the restriction system described in the embodiment (4). The working fluid can move between the port and the limiting device in a closed fluid circuit so as to affect the dimensions of the limiting. Restriction system. (9) In the restriction system described in the embodiment (4). The pressure sensing system measures the pressure of the working fluid and transmits the measured value of the pressure to the external monitor during the adjustment of the limiting device. Restriction system. (10) In the restriction system according to the embodiment (4). The pressure sensing system includes a variable inductance coil adjacent to the deformable surface. The inductance of the coil changes in response to changes in the pressure of the working fluid, The change in inductance provides a measure of the pressure of the working fluid. Restriction system.

(11) In a restriction system for forming a restriction in the patient's body and non-invasively communicating pressure data related to the restriction with an external monitor. A limiting device that is implanted in the patient's body to form a limitation in the body, the limiting device having a variable fluid volume for creating the limitation, and a limiting device. b. A control unit functionally coupled to the limiting device to change the volume of the limiting device. c. A pressure sensing system for measuring the pressure of a fluid in the limiting device and non-invasively communicating the measured pressure with the external monitor, wherein the measured pressure is the stomach. With a pressure detection system, which is proportional to the degree of restriction formed in A restriction system. (12) In the restriction system according to the embodiment (11). The pressure sensing system comprises a mechanically deformable surface in contact with the working fluid. The surface deforms in proportion to the pressure of the working fluid. Restriction system. (13) In the restriction system according to the embodiment (12). The mechanically deformable surface has a mechanical deformation on the surface, and the mechanical deformation is converted into an electrical signal representing the pressure in the working fluid. Restriction system. (14) In the restriction system according to the embodiment (13). The pressure sensing system comprises two or more variable resistance elements mounted on the deformable surface. The resistance value of the element changes in response to the mechanical deformation of the surface. The resistance element is connected to an electric circuit and The output of the electrical circuit provides a measure of the pressure of the working fluid. Restriction system. (15) In the restriction system according to the embodiment (11). The limiting device is an adjustable gastric band, Restriction system. (16) In the restriction system according to the embodiment (13). The pressure sensing system includes a variable capacitance capacitor. The capacitance of the capacitor changes in response to changes in the pressure of the working fluid, The change in capacitance provides a measure of the pressure of the working fluid. Restriction system. (17) In the restriction system according to the embodiment (13). The working fluid can move between the port and the limiting device in a closed fluid circuit so as to affect the dimensions of the limiting. Restriction system. (18) In the restriction system according to the embodiment (13). The pressure sensing system measures the pressure of the working fluid and transmits the measured value of the pressure to the external monitor during the adjustment of the limiting device. Restriction system. (19) In the restriction system according to the embodiment (13). The pressure sensing system includes a variable inductance coil adjacent to the deformable surface. The inductance of the coil changes in response to changes in the pressure of the working fluid, The change in inductance provides a measure of the pressure of the working fluid. Restriction system.

<figref num="1">It is a schematic diagram of the dietary intake restriction device of this invention.</figref><figref num="2">FIG. 3 is a more detailed perspective view of an exemplary implantable portion of the food intake limiting device of FIG.</figref><figref num="3">FIG. 2 is a perspective view of the adjustable gastric band of FIG. 2, showing a gastric band placed around the patient's gastroesophageal junction.</figref><figref num="4">FIG. 2 is a cross-sectional view of the adjustable gastric band of FIG. 2, shown in a deflated state.</figref><figref num="5">FIG. 2 is a cross-sectional view of the adjustable gastric band of FIG. 2, shown in an inflated state to create a dietary intake restriction.</figref><figref num="6">It is a partial cross-sectional side view of the injection port shown in FIG.</figref><figref num="7">It is an isometric view of the holding cover shown in FIG.</figref><figref num="8">It is an isometric view of the pressure sensor shown in FIG.</figref><figref num="9">It is a side sectional view which shows the 1st Embodiment of the pressure detection system of this invention.</figref><figref num="10">It is a simplified schematic diagram of the variable resistance circuit of 1st Embodiment.</figref><figref num="11">It is a side sectional view of the 2nd Embodiment of the pressure detection system of this invention.</figref><figref num="12">It is a block diagram which shows the pressure measuring system which concerns on 1st and 2nd Embodiment of this invention.</figref><figref num="13">It is a side sectional view of the 3rd Embodiment of the pressure detection system of this invention.</figref><figref num="14">It is a block diagram which shows the pressure measuring system which concerns on 3rd Embodiment of this invention.</figref><figref num="15">It is a side sectional view of the 4th Embodiment of the pressure detection system of this invention.</figref><figref num="16">It is a side sectional view of the 5th Embodiment of the pressure detection system of this invention.</figref><figref num="17">It is a block diagram of the pressure measurement system which concerns on 4th and 5th Embodiment of this invention.</figref><figref num="18">It is a figure which shows the graph of the pressure signal from a pressure detection system which appears on an external monitor display during a user inquiry.</figref>

Code description

12 electrical cable assembly 30 Dietary intake restriction system 32 First part 34 patient 36 Second part 38 stomach band 40 stomach 42 injection port 44 catheter 46 Cavity 48 esophagus 50 upper sac 52 Diaphragmatic muscle 60 Pressure reader 62 Electrical cable assembly 64 Control box 66 Display 68 Control switch 70 housing 72 flange 74 Mounting opening 76 bulkhead 80 reservoir 82 Catheter connector 84 sensor 86 maintenance cover 88 First Embodiment 90 Ventilation holes 92 Septum 94 housing 96,98 Strain gauge 100 Wheatstone bridge circuit 102,104 differential amplifier 106 Microcontroller 110 circuit board 112 temperature sensor 114 TET / Telemetry Coil 116 Capacitor 118 Second Embodiment 120 MEMS sensor 122 chamber 126 External control module 130 Primary TET Coil 132 Internal control module 134 TET drive circuit 136 microprocessor 138 memory 140 graphic user interface 142 Primary transceiver 144 Primary Telemetry Coil 146 Downlink alternating magnetic field 150 power supply 152 Ambient pressure sensor 154 skin 156 Secondary TET coil 158 Telemetry Transceiver 160 Rectifier / Power Regulator 162 memory 164 Signal processing circuit 170 Third Embodiment 172 battery 174 Power regulator 176 Internal control module 180 Fourth Embodiment 182 variable capacity 184 First electrode plate 186 Second electrode plate 188 Capacitor mount 190 Induction coil 192 lines 196 Fifth Embodiment 200 variable inductance coil 202 Capacitance 204 line 206 LC resonant circuit 208 Induction coil circuit 210 Induction coil 212 line 214 External module 216 pressure signal