Various embodiments of the present disclosure relate generally to medical devices and related methods. More specifically, particular embodiments of the present disclosure relate to devices and methods for treating the alimentary tract, including, for example, treating gastroesophageal reflux disease (GERD) and obesity.
GERD and obesity are conditions associated with the alimentary tract system. GERD is a condition in which stomach contents leak backwards from the stomach into the esophagus through the lower esophageal sphincter (LES). The leak may be caused by a weak LES or excess gastric pressure. The leaked contents may irritate the esophagus. The irritation may cause heartburn, and could also cause other symptoms. Obesity is a condition where a person's body stores an excess amount of fat, and can be caused by ingesting an excess amount of calories via the alimentary tract system.
Attempts have been made to manage GERD using laparoscopic devices and endoscopic devices. One type of laparoscopic device is a flexible band of interlinked beads with magnetic cores. The flexible band is positioned by laparoscopy around a portion of the esophagus surrounding the LES. The magnetic attraction between the interlinked beads helps keep the band in a contracted state, thus helping the LES resist opening. When food is swallowed, expansion of the esophagus forces the interlinked beads apart, temporarily breaking their magnetic bonds. After the food has passed, magnetic attraction between the interlinked beads is reestablished, thus assisting closing of the LES.
An alternative attempt at managing GERD involves placing a stent having a valve at the LES. The valve assists the LES by reducing or preventing unwanted backflow from the stomach into the esophagus. Another way of assisting closing of the LES involves electrically stimulating tissue at or around the LES to cause the LES to tighten.
Obesity may be managed by electrically stimulating a pyloric sphincter, causing the pyloric sphincter to tighten. Tightening of the pyloric sphincter can slow the rate at which the stomach empties of ingested contents. This may lead to a prolonged sensation of satiety, and a reduced desire for further caloric intake via the alimentary tract system.
Devices for GERD and obesity treatments should be able to differentiate between digestion events like swallowing, stomach contraction, and vomiting. However, current GERD and obesity treatment devices may be imprecise in the way they differentiate between digestion events. As such, the devices may not operate in the manner desired when a digestion event takes place.
In view of the above, the present methods and devices described herein provide improvements in treatments of the alimentary tract, including, for example, GERD and/or obesity treatments.
In accordance with certain embodiments of the present disclosure, an alimentary tract treatment system is disclosed. The system may include a plurality of sensor devices for engaging a wall of a portion of the alimentary tract. The plurality of sensor devices may also sense a parameter of the wall. The system may also include an alimentary tract treatment device for controlling a flow of material through the alimentary tract. Operation of the alimentary tract treatment device may be controlled based on the parameter sensed by the plurality of sensor devices.
In accordance with certain embodiments of the present disclosure, a method for treating gastroesophageal reflux disease (GERD) is disclosed. The method may include sensing peristaltic movement of a portion of an alimentary tract using a plurality of serially arranged strain sensor devices. The plurality of serially arranged strain sensor devices may be mounted on a wall of the alimentary tract. The plurality of serially arranged strain sensor devices may be operatively coupled to a GERD treatment device at a region of the alimentary tract including a lower esophageal sphincter (LES). The method may also include controlling operation of the GERD treatment device based on the sensed peristaltic movement.
In accordance with certain embodiments of the present disclosure, a method for treating obesity is disclosed. The method may include sensing a peristaltic movement of a portion of an alimentary tract using a plurality of serially arranged sensor devices. The plurality of serially arranged strain sensor devices may be mounted on a wall of the alimentary tract. The plurality of serially arranged strain sensor devices may be operatively coupled to an obesity treatment device at a pyloric region of the alimentary tract. The method may also include controlling operation of the obesity treatment device based on the sensed peristaltic movement.
Additional objects and advantages of the disclosed embodiments will be set forth in part in the description that follows, and in part will be apparent from the description, or may be learned by practice of the disclosed embodiments. The objects and advantages of the disclosed embodiments will be realized and attained by means of the elements and combinations particularly pointed out in the appended claims.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the disclosed embodiments, as claimed.
The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate various exemplary embodiments and together with the description, serve to explain the principles of the disclosed embodiments.
Reference will now be made in detail to the exemplary embodiments of the disclosure, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts.
In exemplary embodiments of the present disclosure, GERD and obesity treatments are performed using an alimentary tract treatment system including one or more sensor assemblies, a control unit, and one or more alimentary tract treatment devices. The treatments are initiated by monitoring locations along the alimentary tract using the one or more sensor assemblies. The sensor assemblies generate input signals indicative of sensed strain, or other suitable parameters, at the monitored locations. Next, the control unit receives the input signals and executes one or more algorithms used to determine whether the input signals are indicative of one or more digestive events. Based on the determination, the control unit may send a command signal to the one or more alimentary tract treatment devices. The one or more alimentary tract treatment devices may include one or more valve devices and/or one or more electric stimulation devices for controlling movement of material through the alimentary tract, thereby treating GERD and obesity. Though this description describes treatment devices for GERD and obesity, embodiments of the present disclosure may treat other ailments associated with the alimentary tract.
Exemplary features of the one or more sensor assemblies and the input signals they generate will now be described.
For example, pH sensor assemblies may be used to monitor pH values of alimentary tract fluids, including stomach fluids. pH monitoring may be performed continuously. One or more sensors forming a pH sensor assembly may be mounted on an inner surface of the alimentary tract 10, such as at inner surfaces of the esophagus 12, stomach 14, antrum 18, and/or pylorus 24.
Although strain sensor assemblies may be described in the exemplary embodiments below, it should be understood that any of the types of sensor assemblies may also be used.
The strain sensor assembly 28 may be supported by an outer surface of the esophagus 12 for the purpose of monitoring the esophagus 12. The strain sensor assembly 28 may include a coil 40 and one or more strain sensor devices 52-58. The coil 40 wraps around the esophagus 12 and is spring-biased to exert a compressive force on the esophagus 12, sufficient for keeping the coil 40 in place without interfering with normal esophagus operation. The coil 40 moves with and remains in contact with the outer surface of the esophagus 12 as the esophagus 12 expands and contracts. The strain sensor devices 52-58 are held against the outer surface of the esophagus 12 by the coil 40, and like the coil 40, the strain sensor devices 52-28 move with and remain in contact with the outer surface of the esophagus 12 as the esophagus 12 expands and contracts. Although the strain sensor devices 52-28 are shown as being arranged in a linear fashion on one portion of the outer surface of the esophagus 12 in
The strain sensor assembly 30 and the strain sensor assembly 32 may be mounted on the outer surface of the stomach 14 for the purpose of monitoring the stomach 14. The strain sensor assembly 30 may be supported by a main body 16 of the stomach 14. The strain sensor assembly 32 may be supported by an antrum 18 of the stomach 14.
The strain sensor assembly 30 includes a coil 42 that wraps around the main body 16. The coil 42 is similar to the coil 40 in structure and function. The spring-bias of the coil 42 allows it to move with and remain in contact with the outer surface of the main body 16 as the main body 16 expands and contracts. The strain sensor devices 60-66 are similar to the strain sensor devices 52-58 in structure and function. The strain sensor devices 60-66 are held against the outer surface of the main body 16 by the coil 42, and like the coil 42, the strain sensor devices 60-66 move with and remain in contact with the outer surface of the main body 16 as the main body 16 expands and contracts. While the strain sensor devices 60-66 are shown as being arranged linearly on one portion of the outer surface of the main body 16 in
The strain sensor assembly 32 includes a coil 44 that wraps around the antrum 18, and strain sensor devices 68-74 are held on the antrum 18 by the coil 44. The coil 44 and strain sensor devices 68-74 are similar to the coils 40 and 42 and the strain sensor devices 52-66 in structure and function. As such, the coil 44 and strain sensor devices 68-74 remain in contact with the outer surface of the antrum 18 as the antrum 18 expands and contracts. Two or more of the strain sensor devices 68-74 may be arranged linearly along any portion of the antrum 18. It is also contemplated that the strain sensor devices 68-74 may be split up with one or more of the devices on one portion of the outer surface of the antrum 18, and one or more of the devices on another portion of the outer surface of the antrum 18.
One or more of the coils 40, 42, and 44 may be formed by metal alloys including, for example, stainless steel and/or platinum chromium. These materials may have a desired amount of strength, and also radiopacity. The specific type of or composition of metal alloys may be selected such that movement or deformation of the material, by the alimentary tract 10, may not lead to permanent deformation of the material. It is also contemplated that one or more of the coils 40, 42, and 44 may be formed by biocompatible polymers.
One or more of the coils 40, 42, and 44 may be formed of an assembly including a metal core 43 covered with a silicone layer 45, as shown in
One or more of the coils 40, 42, and 44 may have a substantially circular cross-section, as shown in
Any of the coils 40, 42, and 44 may include one section with one characteristic or set of characteristics, and another section with another characteristic or set of characteristics that is different. For example, one section of the coil may be made of one of the above-described materials, while another section of the coil may be made of another of the above-described materials that is different. It is also contemplated that one section of the coil may have one thickness, while another section of the coil may have a different thickness. It is further contemplated that one section of the coil may have one cross-sectional shape, while another section of the coil may have a different cross-sectional shape.
The strain sensor assemblies 33-36 may be supported by the inner surface of a wall of the stomach 14. For example, one or more of the strain sensor assemblies 33-36 may be implanted on or into the wall of the stomach 14 or otherwise attached to the inner surface of the stomach 14 using endoscopic surgical procedures.
The strain sensor assembly 33 may be placed at or near the junction of the main body 16 and the LES 22. The strain sensor assembly 33 may include a strain sensor device 75 configured to monitor gastric pressure at the junction. While the strain sensor device 75 is shown as being on one portion of the junction in
The strain sensor assemblies 34 and 36 may each include one or more strain sensor devices 84-98 placed along the inner surface of the wall of the stomach 14. The strain sensor devices 84-90 may be placed along the main body 16 of the stomach 14. The strain sensor devices 92-98 may be placed along the antrum 18 of the stomach 14. The strain sensor devices 84-98 move with and remain in contact with the wall of the stomach 14 as the stomach 14 expands and contracts. While the strain sensor devices 84-90 are shown as being placed linearly along particular portions of the inner surface of the main body 16 in
The strain sensor assembly 38 may be supported by a self-expandable stent 46 inserted within the esophagus 12. The strain sensor assembly 38 may be supported by a wall 48 of the stent 46, or by a cover 50 covering the stent 46. The expansion force generated by the stent 46 holds the strain sensor assembly 38 in contact with the inner surface of the esophagus 12, as the esophagus 12 expands and contracts. Two or more of the strain sensor devices 76-82 can be arranged substantially linearly along a portion of the stent 46 and the inner surface of the esophagus 12. It is also contemplated that two or more of the strain sensor devices 76-82 can be arranged around the stent 46 and the inner surface of the esophagus 12 in a substantially nonlinear manner.
The strain sensor devices 52-98 may include one or more fiber Bragg grating (FBG) sensors. A FBG sensor includes a fiber optic cable (not shown) having a central core (not shown) that has a refractory index that is higher than that of a shell (not shown) surrounding the central core. This enables the central core to transmit light via internal reflection. A FBG is generated by creating notches (not shown) within the central core. Light is reflected at specific frequencies as it hits the discontinuities at the FBG. The frequency of the reflected light is a function of strain on the fiber optic cable at the location of the FBG. Thus, the change in frequency can be used to sense a change in strain along the section of the fiber optic cable at the location of the FBG.
It is also contemplated that the strain sensor devices 52-98 may include one or more strain gauges. One exemplary type of strain gauge may be applied to a surface, and may be configured to deform when the surface deforms. Deformation of the strain gauge may produce a change in its electrical resistance. The change in electrical resistance may be monitored, and may be indicative of strain at the surface.
It is further contemplated that one or more of the sensor devices 52-98 may not sense strain or changes in strain, but rather, may sense pH, pressure, and/or force, or changes in pH, pressure, and/or force. While strain forms the basis for generating signals indicative of conditions in the alimentary tract 10 in the exemplary embodiments below, it should be understood that pH, pressure, and/or force may be used to generate similar signals.
Movement of the monitored areas of the alimentary tract section 10, and/or pressure changes in the monitored areas of the alimentary tract section 10, may change the level of strain on the strain sensor devices 52-98. The strain sensor devices 52-98 will generate one or more input signals indicative of strain in the areas in which they are mounted. By comparing strain signals over time, changes in strain at the strain sensor devices can be identified. The magnitudes of any sensed strain changes, the relative timing of any sensed strain changes, and/or the locations of the strain sensor devices 52-98 reporting strain changes may indicate that one or more digestion events (e.g., swallowing, stomach contraction, and vomiting) have occurred.
The strain sensor assemblies 28-38 and their corresponding strain sensor devices 52-98 may be operatively coupled to a control unit (not shown) to provide strain signals to the control unit. The control unit may be implantable or carried on the body. The strain sensor assemblies 28-38 may be coupled to the control unit by wires including, for example, wires extending from one or more of the strain sensor devices 52-98 to the control unit. It is also contemplated that the strain sensor assemblies 28-38 and one or more of the strain sensor devices 52-98 may communicate with the control unit wirelessly via a wireless communications medium.
The control unit may include an input element (not shown) configured to receive the strain signals. Any one of or combination of the strain sensor assemblies 28-38 and their strain sensor devices 52-98 shown in
The control unit may also include a memory element (not shown) configured to store the strain signals and other calculated values. For example, the memory element may include threshold pressure/strain amounts, for comparing to the received strain signals, to determine if one or more digestions events are occurring. Additionally or alternatively, the memory element may include threshold pH, pressure, and/or force amounts, for comparing to received pH, pressure, and/or force signals, to determine if one or more digestion events are occurring.
Threshold amounts or values may be preprogrammed into the memory element, and/or may be determined using one or more of the sensor devices 52-98. For example, with respect to the esophagus 12, one or more of the sensors at or on the esophagus 12 may be used to take baseline measurements when a subject is not eating. For example, baseline measurements may be taken at night. One or more thresholds may be set relative to the baseline measurements. For example, thresholds may be set at five standard deviations from the baseline measurements.
The control unit may also include a processor element (not shown) configured to apply one or more algorithms to the received signals from the sensor devices 52-98, to determine when a digestion event has occurred in the esophagus 12. For example, in one exemplary algorithm, whenever the control unit receives an indication that a plurality of the sensor devices at or on the esophagus 12 have crossed their thresholds, the control unit may evaluate the temporal sequence with which the thresholds were crossed.
If the temporal sequence of crossing moves in a downstream direction of the esophagus 12, the control unit may determine that swallowing is occurring. If the temporal sequence moves in an upstream direction of the esophagus, the control unit may determine that acid reflux or vomiting is occurring.
With respect to the stomach 14, one or more of the sensors at or on the stomach 14 may be used to take baseline measurements during normal gastric digestion. During normal gastric digestion a cyclical pattern of sensed values may be expected. The control unit may use one or more aspects of the cyclical pattern as a reference for normal gastric digestion. For example, during normal gastric digestion cycles, there may be a temporal sequence of strain peaks across sensors from the antrum 18 to the pylorus 24. The control unit may use the strain peak levels and/or timing as a reference or baseline. Strain during a gastric event like vomiting may be greater than strain during normal gastric digestion. Also, during vomiting, strain peaks may occur closer in time, for example almost simultaneously, across multiple sensors, rather than sequentially or farther apart in time as in normal gastric digestion. Thus, using the strain peaks for normal gastric digestion as a baseline, one or more threshold values for strain peak levels and/or strain peak timing may be set that, when crossed, may be indicative of vomiting.
The control unit may also include an output element (not shown) configured to generate a command signal to activate or deactivate at least one of a laparoscopic valve device 102, an endoscopic valve device 104, and electrical stimulation devices 106 and 108 based on the strain signals and/or determinations of digestion event occurrences. It is contemplated that the output element may be in operative communication with one or more of the valve device 102, the valve device 104, the electrical stimulation device 106, and the electrical stimulation device 108, through connecting wires or a wireless communications medium, through which the command signals are transmitted.
It is also contemplated that the control unit may include a power source (not shown) for powering the strain sensor assemblies 28-38, valve devices 102 and 104, and electric stimulation devices 106 and 108.
The laparoscopic valve device 102 is shown in
The endoscopic valve device 104 is shown in
The electric stimulation devices 106 and 108 are shown in
Methods for GERD and/or obesity treatment using at least one of the sensor assemblies 28-38, the control unit, and at least one of the valve devices 102 and 104 and electric stimulation devices 106 and 108, will now be described.
The steps 118-126 of one exemplary method for GERD treatment are shown in
Additionally or alternatively, the control unit may recognize vomiting if readings from the sensors on or at the esophagus 12 cross thresholds, according to a temporal sequence, along an upstream direction of the esophagus 12. It is also contemplated that the control unit may recognize vomiting if one or more of the sensors at or on the stomach 14 experiences a strain peak that exceeds a threshold, and/or experience strain peaks occurring closer in time than would be the case during normal gastric digestion.
When vomiting is recognized by the control unit, the control unit may refrain from assisting closing of the LES 22 (step 124) so that vomiting is not hindered. If the rate of increase is not above the second predetermined level (“NO”), the control unit may interpret the rise in gastric pressure as being a precursor to or indicative of unwanted gastric backflow typical of GERD. Accordingly, the control unit may assist closing of the LES 22 (step 126) to reduce or prevent the backflow.
The steps 128-132 of another exemplary method for GERD therapy are shown in
The steps 134-140 of another exemplary method for GERD therapy are shown in
The steps 142-148 of an exemplary method for obesity treatment are shown in
In the exemplary methods for GERD treatment described above and shown in
In the exemplary method for obesity treatment described above and shown in
Other embodiments of the present disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the embodiments disclosed herein. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the present disclosure being indicated by the following claims.
This application claims the benefit of priority from U.S. Provisional Application No. 61/767,063, filed on Feb. 20, 2013, the entirety of which is incorporated by reference herein.
Number | Date | Country | |
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61767063 | Feb 2013 | US |