WO2002040081A2

WO2002040081A2 - Intragastric balloon device adapted to be repeatedly varied in volume without external assistance

Info

Publication number: WO2002040081A2
Application number: PCT/US2001/051202
Authority: WO
Inventors: Thomas O. Bales; Kevin W. Smith
Original assignee: Syntheon, Llc
Priority date: 2000-11-17
Filing date: 2001-11-13
Publication date: 2002-05-23
Also published as: CA2429234A1; EP1333877A2; AU2002234173A1; US6579301B1; EP1333877A4; WO2002040081A3

Abstract

An intragastic balloon device (10) includes a flexible bladder (12), a relatively rigid reservoir (14) coupled to the bladder and adapted to hold a bladder inflation fluid, and an inflation/deflation system (18) is adapted to move or permit movement of the fluid from the reservoir and into the bladder. The intragastric balloon device (10) is sized such that it may be positioned, in its entirety, into the stomach cavity. Various systems may be used to move or permit movement of the fluid. In several embodiments, the system (18) is a pump (20) which moves the fluid between the reservoir and the bladder. In other embodiments, the system includes a mechanism for heating a fluid to cause the heated fluid to expand the bladder. In yet another embodiment, no reservoir is employed and a pump pumps stomach fluid into the bladder to inflate the bladder. A control mechanism (22) is provided to automatically activate the inflation/deflation system. The automatic activation may be actuivated by a combination of one or more of a timer, the temperature of the stomach, the pressure in the stomach, the mechanical stress in the stomach, or another sensed condition, at which the control system is programmed or otherwise configured to activate. The control system (22) is preferably reprogammable via an external transmitter. In addition, the control system (22) and the pump (20), where utilized, are preferably battery-powered (24) such that the intragastric balloon device is self-contained.

Claims

inserted, in its entirety, into the stomach of a patient through the esophagus . The device is preferably retained in the stomach by its size and shape, which prevent the device from being passed, without physician intervention, by the valves at the entrance and exit of the stomach.

According to the invention, various inflation systems may be used to move or permit movement of the fluid. According to the first embodiment, the inflation system 18 includes a pump 20 adapted to transfer fluid 16 from the reservoir into the bladder 12 to fill the bladder (as shown in Fig. 2), and a control system 22 adapted to control, preferably automatically, operation of the pump 20. The control system 22 may include a timer or one or more sensors and be activated by a combination of one or more of a schedule of the timer, a sensed temperature of the stomach, a sensed pressure in the stomach, a sensed mechanical stress in the stomach, or another sensed condition. Upon activation, the control system 22 assigns power to the pump 20 from the power source of the device, e.g., one or more batteries 24. In addition, the control system 22 can signal the pump 20 to work in reverse in order to return the fluid into the reservoir 14 thereby collapsing the bladder 122 and decreasing the size of the intragastric balloon device or, where a resilient bladder 12 is used, to simply open a valve to permit the return of the fluid.

The batteries 24 of the device are preferably primary cells which are preferably adapted to power the device for the duration of the treatment period. Alternatively, the batteries 24 may be rechargeable and may be recharged through the skin by means of external (outside the body) and internal (within the device) coils. Charging of the batteries may also be performed by radio frequency from an external transmitter. Alternatively, the batteries may be recharged or replaced during an endoscopic procedure.

According to another preferred, though optional, aspect of the invention, the control system 22 is preferably reprogrammable and/or instantly operable via an external transmitter 26 operable by the patient (Fig. 1) . As such, patient discomfort can be alleviated without reliance on sensed conditions by the control system 22.

The above described device, with the pump 20 used to pump fluid from the reservoir 14 into the bladder 12 , permits up to a doubling of the volume of the device without having any compression of the fluid. Alternatively, the pump can compress a gas into the reservoir. Then, the gas can be expanded through the pump or a valve to inflate the bladder. This design permits a greater than two to one ratio of volume, but requires compressing the gas which has increased energy requirements . As such, the pump motor and batteries would need to be relatively larger.

In yet another variation, the fluid is a gas, such as dichlorodifluoroethane, which is liquified in the reservoir by the compressive forces of the pump. The use of such a fluid allows the volume of the reservoir to be reduced and reduces the energy requirements because the pump only has to pump against the constant saturation pressure of the condensing fluid in order to compress the fluid. This is in contrast to the compression of a non-condensing gas in which the pressure continues to rise as the gas becomes more compressed, and which requires greater energy from the pump than in the case of the condensing fluid.

In addition, if the bladder is elastic, it will require less energy to empty back into the reservoir. However, if the bladder is non-elastic it will require less energy to fill. Where an elastic balloon is utilized, a preferred material includes styrene-isobutylene-styrene, which is described in detail in U.S. Patent No. 5,741,331 to Pinchuk.

Turning now to Fig. 3, according to a second embodiment of an intragastric balloon device 110, the energy requirements of the pump 120 can be reduced by adding a spring element 130 which 8

tends to force a sealed piston 132 away from the pump and draw fluid 116 into the reservoir 114. When it is necessary or desired to fill the bladder, the pump 120 is operated by the control system 122 to move the fluid 116 from the reservoir 114 and into the bladder 112 (Fig. 4) . As an alternative to the spring and piston mechanism, the reservoir may include an expanding bellows (not shown) which exerts suction toward the pump.

Referring now to Fig. 5, according to a third embodiment of an intragastric balloon device 210, the bladder 212 may be filled by boiling a fluid 216 located in the reservoir 214. To that end, a heating element 234 is provided in the reservoir 214 and controlled by the control system 222. The reservoir 214 is preferably a relatively poor heat conductor. When the heating element 234 is activated, the fluid 216 is heated and boils, and a gas is released into the bladder 212 to inflate the bladder (Fig. 6) . Then, when the gas cools and condenses, the bladder contracts, and the device resumes the configuration shown in Fig. 5. The bladder 212 is preferably a relatively good thermal insulator so that deflation occurs relatively slowly and so that the inflated bladder 212 does not cause heat damage to the stomach and surrounding organs. In this embodiment, the bladder 212 and reservoir 214 can be an integral structure, as there is no need for a valve or pump therebetween.

Turning now to Fig. 7, in a fourth embodiment, similar to the third embodiment, the reservoir 314 of the intragastric balloon device 310 is thermally conductive, while the bladder 312 is thermally insulative. A valve 320 is provided between the bladder 312 and the reservoir 314. The fluid 316 is chosen to boil at a temperature between just slightly above body temperature and approximately 140°F (the temperature of a hot drink such as tea or coffee) . No heating element is provided within the device.

Referring to Fig. 8, when the patient drinks a hot liquid which is at a temperature at which the fluid 316 boils, the heat H from the liquid heats the reservoir 314 and the fluid 316 within, causing the fluid to boil into a gas, pass through the valve 320, and expand to fill the bladder 312 (Fig. 8) . The bladder 312 remains inflated until the heat of the expanded gas conducts through the bladder, causing the gas to condense and the bladder to contract.

Optionally, a control system 322 may be configured to sense the temperature of the contents of the stomach cavity, and upon sensing a predetermined temperature may open the valve for a timed period to permit the inflation gas to enter the bladder, then close the valve to retain the gas therein, and then re-open the valve to allow the condensed fluid to return to the reservoir. The return of the fluid may be effected by gravity, by compression of the bladder about the fluid, or with a pump.

Alternatively, the valve 320 may consist of two fluid paths : a one-way valve that allows the gas to pass quickly from the reservoir into the bladder, and a restricted return path (with or without a one-way valve) to allow the condensing fluid to return to the reservoir. The return of the fluid may then be aided by gravity, by capillary action (by a very small tube wetted by the fluid or by a tube lined with a wicking material) , or by an elasticity of the bladder that urges the fluid to return to the reservoir.

The above described embodiments may be provided in numerous shapes. For example, referring now to Figs. 9 and 10, the deflated state of the reservoir 414 of the intragastric balloon device 410 may be substantially toroidal, and the bladder 412 may generally form a two-ply membrane across the center of the toroidal reservoir. The reservoir 414 houses the pump 420 and the control system 422. When, by whichever of the above described mechanisms, the bladder 412 is filled and expanded, the intragastric balloon device is provided with a substantially spherical shape. Of course, the intragastric balloon device may be provided in other shapes. For example, the reservoir may be substantially disk shaped with the bladder forming a membrane on