Radially Expandable Gastrointestinal Stimulation Device

Abstract

A fixation device for holding stimulating electrodes in electrical contact with the wall of a portion of the gastrointestinal tract is provided. In one embodiment, the fixation device includes an expandable member that fixes the electrodes in electrical contact with the gastrointestinal tract wall. Also provided is an implantable device and method for controlling the opening and/or closing of the pylorus. In particular a device and method is provided for stimulating the duodenum to control the closing/and or opening of the pylorus. Finally, a method is provided for treating obesity by controlling the pylorus to retain food in the stomach for a desired period of time, among other things to provide a feeling of-satiety and/or to reduce hunger. One aspect includes controlling the pylorus's contraction by electrical stimulation of the duodenum.

1 . A gastrointestinal stimulation device comprising:
 a fixation device comprising a radially expandable member; an outer portion; and   at least one electrode coupled to the outer portion of the fixation device,   wherein the radially expandable member is configured to fix the fixation device within a portion of the gastrointestinal tract so that the at least one electrode is in electrical contact with the gastrointestinal tract.   
     
     
         2 . The gastrointestinal stimulation device of  claim 1  comprising at least one sensor coupled to the fixation device. 
     
     
         3 . The gastrointestinal stimulation device of  claim 2  wherein the at least one sensor comprises at least one of a pressure sensor, an accelerometer, a pH sensor, an impedance sensor, a temperature sensor, or an electrical sensor. 
     
     
         4 . The gastrointestinal stimulation device of  claim 3  wherein the pressure sensor comprises a strain gage. 
     
     
         5 . The gastrointestinal stimulation device of  claim 4  wherein the pressure sensor measures contractions and distention in the gastrointestinal tract. 
     
     
         6 . The gastrointestinal stimulation device of  claim 4  wherein the pressure sensor measures contractions and distention in a duodenum. 
     
     
         7 . The gastrointestinal stimulation device of  claim 4  wherein the pressure sensor measures contractions and distention in an antrum. 
     
     
         8 . The gastrointestinal stimulation device of  claim 4  wherein the pressure sensor detects a human body's satiety. 
     
     
         9 . The gastrointestinal stimulation device of  claim 3  wherein the accelerometer measures a function in gastrointestinal tract. 
     
     
         10 . The gastrointestinal stimulation device of  claim 3  wherein the pH sensor detects the pH of chemicals secreted in a duodenum are secreted in the duodenum during at least one of an onset of hunger or an onset of eating. 
     
     
         11 . The gastrointestinal stimulation device of  claim 9  wherein the impedance sensor comprises an impedance spectrometer. 
     
     
         12 . The gastrointestinal stimulation device of  claim 11  wherein the impedance spectrometer measures chemical constituents of an ingested material. 
     
     
         13 . The gastrointestinal stimulation device of  claim 3  wherein the temperature sensor measures temperature changes in the gastrointestinal tract, such that such that a temperature signal from the sensor is indicative of ingested liquid material within the gastrointestinal tract. 
     
     
         14 . The gastrointestinal stimulation device of  claim 3  wherein the electrical sensor comprises at least one of an electromyogram (EMG) sensor or electrogastrogram (EGG) sensor. 
     
     
         15 . A gastrointestinal stimulation device comprising:
 a fixation device comprising:
 a radially expandable member; 
 an outer portion; and 
 at least one electrode coupled to the outer portion of the fixation device, wherein the radially expandable member is configured to fix the fixation device within a portion of the gastrointestinal tract so that the at least one electrode is in electrical contact with the gastrointestinal tract; 
   at least one sensor coupled to the fixation device, the at least one sensor comprising a pressure sensor, wherein the pressure sensor comprises a strain gage.   
     
     
         16 . A method for treating a gastrointestinal tract of a patient, the method comprising:
 affixing an fixation device within a lumen of the gastrointestinal tract by introducing the fixation device within the lumen, radially expanding a member of the fixation device so that an outer portion of the fixation device engages the surrounding gastrointestinal tract; and   sensing a pressure of the gastrointestinal tract with at least one sensor coupled to the fixation device, by measuring a strain of the fixation device with a strain gage.   
     
     
         17 . The method of  claim 16 , wherein at least one electrode of the fixation device is coupled to the outer portion of the fixation device so that the at least one electrode is in electrical contact with the gastrointestinal tract when the fixation device is expanded therein, and further comprising stimulating the gastrointestinal tract with the electrode.