Apparatus for treating medical conditions of hollow anatomical structures

Related Applications

[0001] The present application is a continuation in part of U.S. Patent Application Serial No. 12/144,575, filed on June 23, 2008, by Edwards et al., entitled "Devices and Methods for Treatment of Hollow Organs," which is a continuation in part of U.S. Patent Application Serial No. 12/108,499, filed on April 23, 2008, by Edwards et al., entitled "Treating Medical Conditions of Hollow Organs," which is a continuation in part of U.S. Patent Application Serial No. 12/099,349, filed on April 8, 2008, by Edwards et al., entitled "Treating Medical Conditions of Hollow Organs;" all of which applications are assigned to the assignee of the present application; the full disclosures of which are all incorporated herein by reference. All patents and published patent applications referred to herein are incorporated herein by reference in their entirety. Technical Field

[0002] The present invention is generally related to devices and methods for treating medical conditions of hollow anatomical structures, and more particularly, and by way of example, to devices and methods for treating the hollow anatomical structures of the digestive system to treat body -weight related conditions.

Background Art

[0003] The human body has several anatomical structures that are considered hollow, such as but not limited to: hollow anatomical structures of the GI tract (e.g., esophagus, stomach, small and large intestines), bladder, ear canal, nasal sinuses, female reproductive system (e.g., vagina, vaginal canal, uterus, fallopian tubes), and the lungs; as well as various veins and arteries.

[0004] Each of these and other hollow anatomical structures can be subject to medical conditions such as cancer or conditions resulting from loosening of the muscles underlying the HAS, tissue proliferation, and the like. Treatment for these medical conditions range from pharmaceutical therapies to highly invasive surgeries.

[0005] As an example, obesity is one major medical condition that affects several hollow structures of the GI tract. Obesity is directly associated with other medical disorders, such as: osteoarthritis (especially in the hips), sciatica, varicose veins, thromboembolism, ventral and hiatal hernias, hypertension, insulin resistance, and hyperinsulinemia; premature death; type 2 diabetes, heart disease, stroke, hypertension, gall bladder disease, GI tract cancers, incontinence, psychological disorders, sleep apnea, gastro esophageal reflux disease (GERD), and liver disease. Reducing obesity reduces the effects of these conditions provided the weight loss is significant and enduring. This, of course, is the challenge to the patient and practitioner.

[0006] Current obesity treatments include behavior modification, pharmaceutical

interventions, and invasive surgeries.

[0007] One problem with behavior modification is patient compliance. Significant and maintained weight loss demand enormous levels of patient compliance over a long time.

[0008] Problems with pharmaceutical intervention include drug dependence and adverse side effects. Amphetamine analog treatments involve habitual use of addictive drugs to produce and maintain significant weight loss. Dexfenfluramine and fenfluramine treatments often result in primary pulmonary hypertension and cardiac valve abnormalities. Drugs such as sibutramine substantially increase blood pressure in many patients.

[0009] Surgical obesity treatments include invasive surgical procedures such as: gastric banding, bariatric surgery, and liposuction. While current surgical procedures can be effective, the overall rates of surgical mortality and associated hepatic dysfunction are so high that surgical treatments are only indicated for younger patients who are morbidly obese.

[0010] The following table outlines various conventional treatments for obesity and issues associated therewith:

[0011] USP 7,326,207 proposes treating obesity by mapping (for example, using a visualization apparatus, such as but not limited to endoscopes or fluoroscopes) and ablating nerves in targeted stomach areas by creating patterns of thermal lesions. The nerves are ablated using electrodes that penetrate the nerves during energy application. Mapping is required to properly position the electrodes where they can penetrate the nerves.

Physiological changes caused by tissue ablation create a sense of satiety in the patient by directly modulating nerves responsible for hunger sensation or by modulating the nerves inhibiting the let-down reflex of the stomach muscles that are digestion precursors.

[0012] Despite the treatment described in the '207 patent, there is room for further improvement in the field of obesity treatment and as well treatment of other medical conditions that affect hollow anatomical structures.

Summary

[0013] The present invention relates to devices and methods for treatment of hollow anatomical structures ("HAS"). In an embodiment, the present invention relates to devices and methods for treatment of the digestive system, such as the stomach, for weight-related conditions. Although the apparatus and methods of the present invention are described in the context of treating the stomach, it should be appreciated that the present devices and methods are applicable and useful in treatment of other hollow anatomical structures and may be adapted to suit the particular hollow anatomical structure under treatment. Exemplary hollow anatomical structures include, but are not limited to, the lungs, urinary tract, nasal passages, the reproductive tract, as well as body lumens and blood vessels such as, but not limited to, the perforator veins which connect the superficial veins to the deep veins in the leg, truncal superficial veins of the leg (e.g., great saphenous vein, short saphenous vein, and the like), superficial tributary veins of the leg, internal spermatic veins (varicoceles), ovarian veins, gonadal veins, hemorrhoidal vessels, fallopian tubes, a-v malformations, a-v fistula side branches, esophageal varices, and the like. [0014] Methods of treatment embodying features of the present invention include applying energy to, among other things, any one or more of muscles, nerves, mucosa (or tissue), or glands associated with and/or underlying the hollow anatomical structure (including vessels) to alter any one or more of the muscular profile of the structure, its biomechanical operation, or physiological properties (e.g., shrinkage, coagulation, ablation, constriction). The treatments embodying features of the present invention enable the modification of any one or more of the nerve signal transmission, muscle profile to one more suitable for reaching treatment goals, or the gland's enzyme release. As used herein, the term "ablative energy" denotes energy to bring about any of such physiological or other changes mentioned above.

[0015] In each such application and others to treat the various hollow anatomical structures, the point of entry for the introduction of the present devices to access the structures, the accompanying components (e.g., visualization device), physical shape of the delivery system, as well as the treatment assembly embodying features of the present invention may differ to suit the particular application. The present apparatus and methods may be adapted for use in percutaneous, surgical, or laparoscopic procedures.

[0016] In the case of the stomach, the desired treatment sites of the hollow anatomical structure, are those of the stomach's and include any one or more areas corresponding to or in the vicinities of the greater curvature of the stomach, smaller curvature of the stomach, cardiac zone, gastric/fundic zone, pyloric zone, or the vagal nerve within the stomach. In an embodiment, the treatment site may include the small intestine. In an embodiment, the nerves, muscles, and/or glands are exposed to a source of ablative energy by expanding the structure beyond its normal volume until the structures mucosa (or tissue) is separated and the underlying nerves, muscles, and/or glands are exposable to the energy. The nerves, muscles, mucosa, and/or glands are exposed by way of expanding an expandable member ("expander member") sized and configured to expand within the structure, and conforming the structure's inner volume to that of the expanded member. In one embodiment, the expandable expander member is formed from non-compliant or semi-compliant material such that it cannot at least substantially expand beyond a pre-defined size. The expandable member, upon expansion, expands the structure to a size greater than its normal (e.g., as it is at least prior to the treatment) size, thus conforming the hollow structure's volume to that of the expandable member in the expanded configuration. The methods of treatment provide for guided delivery of energy to the desired treatment areas of the hollow anatomical structure.

[0017] An apparatus for treating a hollow anatomical structure includes an expandable member, adapted for expansion within an interior of the hollow anatomical structure and conforming the structure to a profile of the expandable member in the expanded

configuration. The structure expander member comprises treatment areas corresponding to desired target treatment areas of the structure. The treatment regions include magnetic regions adapted for sensing by a magnetic sensor. The apparatus further includes energy delivery regions adapted to deliver ablative energy to one or more of the desired target treatment sites of the hollow anatomical structure. The magnetic sensors are adapted to sense the magnetic regions and to send a signal for delivery of ablative energy by the energy delivery regions. The energy delivery regions may include one or more electrodes. In an embodiment, the sensing member comprises an expandable member disposed within an interior of the expander member. In an embodiment, the energy delivery regions and the magnetic sensors are disposed on, in, or about the same expandable sensing member.

[0018] In an embodiment, an apparatus for treating medical conditions of hollow anatomical structures embodying features of the present invention may include a treating assembly having an expander assembly including an expandable expander member configured for expansion in the structure to expose at least a portion of either or both the hollow structure's underlying nerves or muscle. In an exemplary configuration, the expandable member, such as an expandable balloon, is disposed at a distal end of an elongate body such as a catheter.

[0019] The expandable expander balloon includes treatment areas corresponding to any one or more of desired treatment sites of the HAS. In the case of the stomach, the desired treatment sites are those of the stomach's as described earlier. In an embodiment, the expander balloon may extend into the small intestine to provide treatment to at least a portion of the small intestine. The expander balloon treatment areas include magnetic regions corresponding to one or more of the treatment sites of the HAS and are which adapted to transmit ablative energy delivered from an energy source to the desired surfaces of the structure. The magnetic regions are adapted for being sensed, directly or indirectly, by one or more magnetic sensors or providing information as to the presence of the magnetic regions to the magnetic sensors. Expansion of the expander balloon expands the stomach to stretch the pleated mucosa of the stomach and expose underlying nerves and stomach muscle, and to bring into surface contact the treatment site with the magnetic regions.

[0020] The magnetic regions comprise magnetic material disposed on either side of a surface of the expander balloon, magnetic material integrated with the material forming the expander balloon, or material disposed between layers of material forming the balloon as for example when the balloon is formed from multiple layers. The magnetic regions may be disposed circumferentially or longitudinally about the expander balloon and may be continuous or include multiple regions with interruptions. The shapes of the regions may be uniform throughout or different regions may have different shapes.

[0021] The magnetic material may be formed from any one or more suitable materials.

Exemplary magnetic materials include, but are not limited to: ceramic, or ferrite, magnets; alnico magnets; ticonal magnets; composite magnets of various types of resin and magnetic powders. The magnetic material, preferably comprises a ferrous metal compounds.

[0022] A sensor assembly comprising a sensor member includes the magnetic sensors adapted to sense the magnetic regions when disposed at or in the near vicinity of the magnetic regions. Energy delivery regions, such as electrodes, are associated with the magnetic sensors. Upon sensing of the magnetic regions by the magnetic sensors, the magnetic sensors enable the delivery of ablative energy to the energy regions (e.g., electrodes). In operation, energy from the electrodes is transmitted to the treatment areas of the expander member which is in surface contact with the inner surface of the stomach. In an embodiment the sensor assembly is adapted for disposal within an interior of the expander balloon.

[0023] In an embodiment, the treatment assembly comprises the expander member disposed at a distal end of an elongate member, such as a catheter. The expander member may be expanded by, for example, inflation fluid deliverable through suitable conduits such as an inner lumen of the expander catheter.

[0024] In an embodiment, the sensor assembly comprises a sensor member such as an expandable balloon disposed at a distal end of an elongate member. The sensor balloon and a distal portion of the sensor elongate member are adapted for disposal and navigation within the interior of the expanded expander balloon. Magnetic sensors adapted to sense the magnetic areas of the expander member are disposed at, on, in, or about the sensor balloon. The sensor balloon further comprises energy regions. In an embodiment, the energy regions comprise electrodes for delivering ablative energy to the desired target sites of the stomach. In operation, upon the sensor member being disposed within the interior of the expanded expander member and being brought into close proximity of the magnetic sensors, the magnetic sensors sense the presence of the magnetic regions. The magnetic sensor member transmits a signal to a controller assembly locatable outside the patient's body. The controller transmits a signal to the energy regions, such as the electrodes, enabling the delivery of ablative energy to the expander assembly (e.g., magnetic regions). Ablative energy is transmitted from the expander member to the desired target treatment sites. In an embodiment, the electrodes are adapted for surface contact with the magnetic regions. The sensor member may be expanded by, for example, inflation fluid deliverable through suitable conduits such as an inner lumen of the sensor elongate member.

[0025] In an embodiment, the electrodes are disposed in close proximity of the magnetic sensors. Electrodes and magnetic sensors by way of leads (not shown), which may be independent of one another, are in communication with an energy source and a processor which are normally associated with the external control assembly. Upon expansion (e.g., inflation by way of an inflation fluid directed through the lumen of the sensor elongate member) of the sensor balloon, the sensor balloon extends outwardly from the distal end of the sensor elongate member and may be navigated inside the extender balloon. The sensor elongate member adapted for flexible movement is movable around the interior of expander balloon. The sensors are adapted such that as they are disposed at or in the near vicinity of the magnetic regions, the sensors sense the presence of the magnetic regions and transmit a signal to the processor. A signal is transmitted from the control assembly to the energy generator and the energy source transmits/provides energy to energy regions, such as electrodes. Electrodes are brought into surface contact (preferably non-penetrating) with the magnetic regions, and transmit ablative energy to the expandable balloon and the target treatment sites of the stomach. This enables guided delivery of ablative energy to the tissue or nerves at the desired target sites of the hollow anatomical structure.

[0026] The sensor assembly may further be adapted to receive an optional visualization device, such as an endoscope within interior of the sensor elongate member.

[0027] The endoscope may include an illumination source such as lights for visualization of the structure when it is disposed within its interior. In an embodiment, the endoscope, is disposed within the expander assembly prior to advancement into the structure. The expander assembly, the sensor assembly, and the endoscope are accessible through a handpiece disposed at a proximal end of the treatment assembly.

[0028] The source of energy may be energy in the form of electromagnetic energy (e.g., RF, microwave), ultrasonic energy, infrared energy, visible laser energy, heat energy, or the like.

[0029] In an embodiment, a distal portion of the expander balloon may be shaped, upon expansion, to be similar to a portion of the HAS, preferably, distal to the desired treatment site. In the case of stomach, the shaped distal portion, upon expansion, seats against the distal end of the pyloric sphincter. [0030] In an embodiment, the source of energy is energized fluid such as hot water, saline, steam, or the like. The sensing balloon may or may not include electrodes. Similarly, upon receipt of signal to deliver ablative energy to the sensing balloon, energized fluid is delivered into an interior of the sensing balloon. The sensing balloon, as is brought into physical contact with the magnetic regions, transmits ablative energy to the magnetic regions and the desired target treatment sites.

[0031] In an embodiment, other sensing methods and apparatus may be used. By way of example, the expander member may include ultrasonic regions which differ in their properties from other portion of the expander member. The ultrasonic regions, similar to the magnetic regions, correspond to the target treatment sites of the anatomical structure. An ultrasonic sensor member, once disposed at or near the ultrasonic regions, enables the delivery of energy to energy regions, such as electrodes. Similarly, energy is delivered to the ultrasonic regions of the expander balloon and is transmitted to the desired target treatment sites of the anatomical structure.

[0032] The external control assembly provides and controls the various operations of the apparatus, including the treatment assembly (e.g., expander assembly, sensor assembly, visualization assembly, and energy assembly). The energy sources is provided and controlled by an energy generator controllable by the control assembly. The amount and level of energy at its source is set to provide a sufficient level of energy at the point of treatment to effectuate the desired treatment. The temperature at the point of treatment, for the stomach, may range from about 50 to about 100 ^° C, from about 60 ^° to about 95 ^° C, from about 60 ^° to about 80 ^° C.

[0033] In order to monitor the amount of energy delivered and the amount of heat generated, the apparatus may also include one or more sensors. The one or more sensors may be located within or about the expander member, at or near the magnetic regions; the sensor member, or any other suitable location. These sensors can be used to detect a variety of operating parameters including the amount of energy delivered, and the temperature of a region adjacent the apparatus. These sensors can also be used to provide feedback for controlling the operation of an energy source which delivers energy to the energy transmitting regions. In addition, chemical or biochemical sensors can be used to detect ablation.

[0034] In one embodiment, the at least one temperature sensor is a thermocouple or thermistor. The temperature sensor is coupled to a communication link (such as a conductor), which is coupled to a processor. For example, in the case where the temperature sensor is a thermocouple, the communication link may comprise a D/ A converter coupled to a register disposed for reading by the processor. The processor reads a sensor value from the sensor and, responsive thereto, controls the signal generator so as to achieve delivery of an effective amount of energy to a desired section of tissue to be ablated. The processor thus uses the information from the signal generator, the energy transmitting regions, and temperature sensor, as a feedback loop for controlled delivery of energy to a section of a stomach (or other treatment areas of a hollow anatomical structure). For example, the processor may control the level of energy to achieve a selected temperature, or to achieve a selected amount of ablation of a section of a stomach. A variety of positionings for the sensors are possible. In one embodiment, the sensor is coupled to the expander member (e.g., magnetic regions) and/or the sensor member.

[0035] As described above, the temperature or some other property of the tissue being ablated, or of the energy delivery device can be monitored using a variety of sensors. By way of example, open and a closed loop feedback systems may be utilized for coupling a sensor used in the apparatus to an energy source so that the output energy of the energy source is adjusted in relation to the property sensed by the sensor. It should be appreciated that the sensor may take any appropriate form, as for example formed of wireless construction, and may further be configured to sense and convey the necessary information in any number of ways and formats and is not limited to direct thermal sensors. By way of example and not limitation, the temperature may be sensed by optical means which can assess a change in the color of at least a portion of expander member (e.g., magnetic regions). In this configuration, colorants may be present in the material forming the expander member/regions (or the sensor member, e.g., the energy regions) or be painted or deposited on its material (on the inner or outer surface). Once the colored area is exposed to the elevated temperature, the colorant may change its characteristics. Information as to the temperature may then be conveyed to the practitioner. The information may be conveyed automatically by instrumentation or by direct visualization through the endoscopic device.

[0036] The expander member and the sensor member may be formed, independently, from any suitable material such as, but not limited to expandable, noncompliant (or semi- compliant) material including Mylar, Nylon, PET, PeBax, IEBA, or a combination thereof. In a preferred embodiment, the material for balloons is formed, independently, from non- compliant material. For example, Mylar, while expandable, is noncompliant and restricts expansion of the expandable balloons within the stomach. Therefore, an expandable balloon formed from Mylar cannot infinitely expand and patient injury resulting from unintended over-inflation of expandable balloon 320 can be reduced. In an embodiment, when used for obesity treatment, expandable expander balloon is constructed such that when inflated within the stomach, the stomach expands from its empty volume (about 1 liter) to at least about twice the stomach's empty volume (e.g. 2 liters). However, for other hollow anatomical structures and other species, the expandable member may have different profiles or volumes. In an embodiment, the expander balloon is pre-shaped such that as the expander member is expanded within the hollow anatomical structure, the interior of the hollow anatomical structure conforms to the profile of the expandable member.

[0037] Optional visual markings, corresponding to desired target areas of the HAS, may be located on the expander member (e.g. magnetic regions) and/or the sensor member. The visual markings are used to aid in locating the desired treatment target areas. Such visual markings may be incorporated into or deposited on or within the material forming the member. In an embodiment, the visual markings may take the form of colorant, metallic or polymeric material. Although some sort of visual marking may be preferred, the practitioner may identify the necessary areas for transfer of energy using practitioner' s experience. The visual markings may be positioned to correspond to any one or more areas corresponding to or in the vicinities of the greater curvature of the stomach, smaller curvature of the stomach, cardiac zone, gastric/fundic zone, pyloric zone, or the vagal nerve within the stomach.

[0038] In another embodiment, a treatment assembly may include a reference point positioner disposed at a distal end of the expander assembly. Preferably, reference point positioner comprises a positioning balloon adapted for inflation in the patient's body using means such as a conventional air or liquid tube that may also acts as a catheter guide. In operation, positioning balloon is inflated after passing through the pyloric sphincter and seats against the distal side of the pyloric sphincter. Once seated, inflated positioning balloon sets a reference point for tube and allows proper positioning of the balloon assembly without necessarily using a visualization apparatus.

[0039] In an embodiment, the expander balloon and its treatment sites may extend into the small intestine to provide treatment to at least a portion of the small intestine.

[0040] In an embodiment, the external treatment controller includes any one or more of the following subassemblies: treatment energy source for providing and controlling energy source, input/output (I/O) device, inflation fluid delivery unit for inflating/deflating the expandable members, and/or a positioning balloon when present. The desired energy levels differ for different hollow anatomical structures. [0041] In an exemplary method for treating the hollow anatomical structures embodying features of the present invention includes using a source of energy to apply energy to at least one surface of the HAS to affect its operation. In an embodiment energy, is thermal energy provided from a source of energy in the form of electromagnetic energy (e.g., RF, microwave), ultrasonic energy, infrared energy, visible laser energy, heat energy, or the like.

[0042] In an embodiment, the hollow anatomical structure is the stomach and the at least one surface of the HAS to which energy is applied is either or both stomach's muscle surface or the surface in the vicinity of at least a portion of a nerve communicating with the stomach and brain. In an embodiment, the treatment includes applying energy to at least one surface of the stomach's underlying glands to affect glandular emissions, such as ghrelin, pepsin, rennin, and/or HCl.

[0043] Exemplary methods embodying features of the present invention, for treating the hollow anatomical structure, such as the stomach in the digestive tract include, introducing a hollow anatomical structure expander member into the interior of the hollow anatomical structure and expanding the expander member to conform the interior of the hollow anatomical structure to the profile of the expanded expander member.

[0044] The expander member comprises treatment areas including magnetic regions corresponding to one or more of the treatment sites of the HAS and which are adapted to transmit ablative energy delivered from an energy source to the desired surfaces of the structure. In an embodiment, the expander balloon expands the stomach to stretch the pleated mucosa of the stomach and exposes underlying nerves and stomach muscle, and brings into surface contact the treatment site with the magnetic regions.

[0045] A magnetic sensor member is introduced into an interior of the expander member and is navigated within the interior of the expander member. In an embodiment, the sensor member is brought into surface contract with the expander member. The magnetic regions are sensed and the sensor member transmits a signal enabling the delivery of energy from an energy delivery region to the magnetic regions or regions in close proximity thereof. In an embodiment, the magnetic sensors transmit the signal to an external control assembly which enables the transmission of a control signal to an energy generator for providing a source of energy to the energy delivery regions. In an embodiment, the energy delivery regions are electrodes. In an embodiment, the magnetic sensors and the energy delivery regions are located at, on, in, or about the same member, such as an expandable balloon.

[0046] The source of energy, such as RF energy, is controllably provided, to the energy regions, such as the electrodes. In an embodiment, the electrodes are brought into surface contact with the magnetic regions. The ablative energy is transmitted from the electrodes to the expander member, such as the magnetic regions and to the interior of the hollow anatomical structure. In an embodiment, when the energy is by way of energized fluid source, such as water, saline, or the like, the energized fluid is delivered into an interior of the sensor balloon (e.g., the expandable member comprising the magnetic sensors).. The energy delivery regions are brought into surface contact with the magnetic regions. Ablative energy is transmitted from the energy regions to the magnetic regions and the interior surface of the hollow anatomical structure. At least one or more of underlying nerve, muscle, or gland of the stomach are treated (e.g., ablated). In an embodiment, the at least one or more of underlying muscle is at least in one of the greater curvature of the stomach, smaller curvature of the stomach, cardiac zone, gastric/fundic zone, pyloric zone, or the vagal nerve within the stomach.

[0047] In an embodiment for treatment of the gastric tract, and in operation, a gastric introducer is positioned in the patient's throat and protects the esophageal walls during the procedure.

[0048] The expander assembly, preloaded with the sensor assembly and the endoscope (when present) is inserted into patient's body through the introducer. The expander balloon is advanced distally positioning the shaped distal portion against the distal side of the pyloric sphincter. Using an inflation fluid line, such as an air line through a hand-piece disposed at the proximal end of the HAS treatment assembly, the expander member is inflated until the stomach's volume reaches the desired volume, such as at least about twice its empty volume (e.g. to about 2 liters). The pre-shaped distal portion, at the expanded configuration, seats against the distal side of the pyloric sphincter, providing an anchor and aiding in position and placement of the expander assembly within stomach.

[0049] Once the expander member is expanded, the treatment regions including the magnetic regions are disposed at the desired target areas of the stomach (or other hollow anatomical structure).

[0050] The sensor balloon with the sensors is extended out from the distal end of the sensor elongate member. In an embodiment, the sensor balloon is extended from the distal end of the sensor elongate member upon being inflated with an inflation fluid (e.g., deliverable through the lumen of the sensor elongate member). With assistance of the endoscope, when present, the sensor balloon is navigated within the interior of the expander balloon. As the sensors are disposed at or in the near vicinity of the magnetic regions, the sensors sense the presence of the magnetic regions and transmit this information to the processor. A signal is transmitted from the control assembly to the energy generator and the energy source transmits/provides energy to energy regions such as the electrodes disposed on, in, or about the sensor balloon. The electrodes are brought into (preferably non-penetrating) surface contact with the magnetic regions of the expander balloon which then transmit the ablative energy to the desired target treatment sites of the stomach.

[0051] In an embodiment, the treatment regions of the sensor balloon are the balloon itself. Energized fluid such as hot water, steam, saline, and the like is delivered into the sensor balloon. The sensor balloon extends out from the distal end of the sensor elongate member. The sensor balloon is navigated within the stomach. Upon sensing of the magnetic regions of the expander balloon, the sensor balloon (including the hot fluid) is brought into contact with the magnetic regions. Ablative energy is transferred from the magnetic regions to the desired target tissue sites of the stomach.

[0052] As stated earlier, the energy may be in the form of electromagnetic energy (e.g., RF, microwave), ultrasonic energy, infrared energy, visible laser energy, heat energy, hot fluid or the like. During the treatment period, using GUI and feedback from corresponding sensor associated with such magnetic regions, the practitioner can monitor the temperature at the site. The duration of time and frequency of applied energy are, of course, responsive to judgments of medical personnel.

[0053] After the practitioner is satisfied that the desired amount of tissue has been treated (for example ablated) and/or the pulse transmissions between nerves and the brain have been affected by the desired amount, energy application is stopped. The sensor balloon and the expander balloon are deflated, and the sensor assembly, expander assembly, and the endoscope are withdrawn from the patient, as is the gastro introducer.

[0054] In another embodiment embodying features of the present invention, after patient sedation, the reference point positioner (e.g., reference point balloon) is introduced into the patient's alimentary canal. The positioning balloon is advanced through the stomach and onto the distal side of the pyloric sphincter. The positioning balloon is inflated to seal against the distal side of the pyloric sphincter. This sets a fixed reference point for the tube. A gastric introducer positioned in the patient's throat, protects the esophageal walls during the next steps in the process. The expander assembly, sensor assembly, and the endoscope are introduced into the hollow anatomical structure. The desired target areas are treated as described above.

[0055] The extender assembly is now introduced into the patient's digestive system through the gastric introducer and by the catheter riding over tube. When distal tip of the catheter contacts the positioning balloon and the closed pyloric sphincter, the practitioner stops inserting the stomach expander into the patient. Balloon member is then inflated until the stomach's volume becomes about twice its empty volume.

[0056] The practitioner, using same or similar methodology as that described above treats the desired areas of the hollow anatomical structure. After the practitioner is satisfied that the desired target sites have been treated, energy application is stopped. The reference positioner, the expander balloon, and the sensor balloon are deflated and withdrawn long with the endoscope from the patient, as is the gastro introducer.

Brief Description of Drawing

[0057] FIGs. IA and IB are simplified illustrations of a mammalian digestive system.

[0058] FIG. 2 illustrates an exemplary assembly embodying features of the present invention for treating hollow anatomical structures.

[0059] FIGs. 3 A and 3B are schematic representations of different expander members embodying features of the invention.

[0060] FIGs. 3Al, 3A2 and 3 A3 are schematic cross sectional views of exemplary expander members of FIG. 3 A embodying features of the invention having magnetic regions.

[0061] FIG. 4A is a schematic representation of a sensor assembly embodying features of the invention.

[0062] FIGs. 4AA and 4AB are schematic cross sectional views of the sensor assembly of

FIG. 4A.

[0063] FIGs. 4B1-4B4 and 4C1-4C4 are exemplary sensor assemblies embodying features of the invention.

[0064] FIG. 5 A is a schematic representation of a treatment assembly embodying features of the invention and for treating a hollow anatomical structure.

[0065] FIGs. 5AA and 5AB are cross sectional views of portions of the HAS expander assembly, sensor assembly, endoscope, and the introducer of FIG. 4 A.

[0066] FIG. 5B is a schematic representation of another treatment assembly embodying features of the invention and for treating a hollow anatomical structure.

[0067] FIG. 6 illustrates a schematic of an exemplary external control unit embodying features of the invention for use with the stomach treatment assembly of FIG. 4 A.

[0068] FIGs. 7 A and 7B are schematic representations of neural communication between the stomach and the brain.

[0069] FIG. 8 illustrates a schematic profile of a treated stomach about 8-12 weeks, post-op.

Description of Embodiments

Anatomical Background

[0070] In describing features of the present invention, the hollow organ of the digestive system, such as the stomach, will be used. However, it should be appreciated by those skilled in the art that the use of this exemplary organ is not intended to limit the scope of the present invention.

[0071] FIGs. IA and IB are simplified depictions of a mammalian digestive system. These FIGs. are not intended to be strictly accurate in an anatomic sense or imply that the teachings of this patent application are limited strictly to treating the digestive system. The drawings show the digestive system in somewhat diagrammatic form for purposes of discussion.

[0072] FIG. IA, illustrates esophagus 10, a muscular tube, for carrying food from the mouth to the stomach 12, by way of wavelike contractions of the muscles in the walls of the esophagus 10. The interior esophagus walls include glands that secrete mucus, which further aid the movement of food by acting as lubricants.

[0073] Stomach 12, located in the upper left hand side of the abdomen, lies between the esophagus 10 and the small intestine 14. In humans and most other animals, stomach 12 is a simple baglike organ.

[0074] FIG. IB depicts branches 15 of the vagal nerve that connect stomach 12 with the hindbrain H which is believed to be the neurological source for the hunger sensation. The upper end of stomach 12 connects with the esophagus 10 at cardiac notch 16 (FIG. IA). The muscular ring called the lower esophageal sphincter 18 surrounds the opening between the esophagus 10 and the stomach 12. The funnel-shaped region of the stomach 12 immediately next to sphincter 18 is the cardia. The cardia (also known as Z-line or esophagogastric junction or gastroesophageal junction) is the anatomical term for the junction orifice of the stomach and the esophagus. At the cardia, the mucosa of the esophagus transitions into gastric mucosa. The cardia is also the site of the lower esophageal sphincter 18 (LES which is also termed cardiac sphincter). The greater curvature of the stomach, 26, starts from the cardiac orifice at the cardiac notch, and forms an arch backward, upward, and to the left; the highest point of the convexity is on a level with the sixth left costal cartilage. The lesser curvature 27 of the stomach is opposite the greater curvature and extends between the cardiac and pyloric orifices, forming the right or posterior border of the stomach. It descends as a continuation of the right margin of the esophagus in front of the fibers of the right crus of the diaphragm, and then, turning to the right, it crosses the first lumbar vertebra and ends at the pylorus.

[0075] From this level it may be followed downward and forward, with a slight convexity to the left as low as the cartilage of the ninth rib; it then turns to the right, to the end of the pylorus. Positioned below the cardia is the fundus 25 of the stomach.

[0076] The volume of an average adult stomach, an organ for storing and digesting food, is a little over one quart (-0.95 liter). Pyloric sphincter 22, located distal of pylorus 23, surrounds and controls the size of the duodenal opening disposed between stomach 12 and small intestine 14. Pyloric sphincter 22 keeps non-liquid food in stomach 12 until the food is processed into a more flowable liquid form, thereafter allowing for the flow of the liquefied food from stomach 12 into the intestine 14. The time food spends in stomach 12 varies and usually ranges from about three to about five hours.

[0077] Using these anatomical features as landmarks or guides, the human stomach is often described as having three zones, namely: cardiac zone, gastric/fundic zone, and pyloric zone. In an embodiment, A treatment according to the body -weight related conditions, according to the present invention, is achieved by applying energy to or in the vicinities of any one or more of:

[0078] (1) nerve tissue which allows nerve pulse communication between the hindbrain H and stomach 12; or

[0079] (2) stomach tissue to ablate tissue in one or more areas where food is either processed and/or absorbed by the body, for example, the cardiac, gastric/fundic, and pyloric zones.

[0080] Additionally, treatment may be expanded to other areas, such as the small intestine (and associated nerves), where about 95% of all food absorption occurs. Ablation, or causing cell death, produces lesions which when large enough, evoke tissue-healing and intervention of fibroblasts, myofibroblasts, macrophages, and other cells. Healing results in tissue contraction (shrinkage), decreased volume, and/or altered biomechanical properties. In contrast with other treatments for conditions such as obesity which merely try to prolong patient satiety, the current devices and methods embodying features of the present invention, further provide for directly affecting the digestive process and may reduce food absorption. Without intending any limitations on the scope of the present invention, it is believed by the present inventors that ablation of cells in the cardiac, gastric/fundic, and/or pyloric zones enables treatment of weight-related conditions and reduces a patient's body weight, among other things, for the following reasons:

[0081] CARDIAC AND FUNDIC-GASTRIC ZONES - The cardia and fundic-gastric zone contain, respectively, the cardiac glands (not shown) and the fundic glands (not shown). The cardiac and fundic glands release digestive enzymes (e.g., ghrelin, pepsin and rennin) and hydrochloric acid (HCl) which are used during digestion to break down food. Ablating a portion of the cardiac and gastric-fundic zones, e.g., the cardiac and fundic glands, therefore, reduces the release of ghrelin, pepsin, rennin and HCl, thereby reducing the amount of food digested by the body and resulting in more undigested food particles passing through the patient's body.

[0082] PYLORIC ZONE - The pyloric sphincter controls the size of food particles and their flow from the stomach (emptying cycle). The wider the opening of the sphincter, the larger the size of the food particles that may flow out of the stomach. Without limiting the scope of the present invention, it is believed that ablating the pyloric muscle tissue decreases the size of the pyloric opening and the size of food particles that may flow out, thereby lengthening the emptying cycle (longer sensation of satiety).

[0083] The gastric zone also includes the lesser curvature of the stomach which contains nerves that control peristalsis of the stomach walls. Peristalsis contributes to digestion by physically reducing the size of food particles in the stomach. It is also believed, without limiting the scope of the present invention, that ablating portions of the muscles of the lesser curvature reduces peristalsis and increases food particle size. These larger food particles, when passed through the pyloric sphincter, cannot be digested through the small intestine and therefore would pass through the patient's body undigested. Finally, ablating gastric zone tissue may also affect the gastric glands and reduce HCl production in the stomach (see above).

[0084] Against this anatomical and physiological background, exemplary apparatus, assemblies, and methods for treating body -weight related medical conditions associated with the digestive hollow organs will be described. It should be appreciated by those skilled in the art that using the digestive hollow organ, such as the stomach, for describing features of the present invention, is not intended to limit the scope of the present invention.

Treatment Apparatus [0085] FIGs. 2 through 6 show features of an exemplary embodiment of apparatus 80 for treating hollow anatomical structures ("HAS").

[0086] Assembly 80 (FIG. 2) includes a hollow anatomical structures treating assembly 100 (FIGs. 5 A and 5B) and an external control assembly 500 (FIG. 6). At least a portion of the HAS treating assembly 100 works inside the patient's body for treatment of the hollow anatomical structures such as hollow organs and blood vessels. External control assembly 500 (FIG. 6) includes components for, among other things, controlling, monitoring, and viewing, at least parts of the HAS treating assembly 100. For purposes of describing the present invention the digestive tract, e.g., stomach 12 (FIGs. IA and IB) will be used.

Although the apparatus and methods of the present invention are described in the context of treating the digestive tract (e.g., stomach), it should be appreciated that the present devices and methods are applicable and useful in treatment of other hollow anatomical structures. Furthermore, it should be appreciated that the shape, size, and specific configuration of the various components may be modified and adapted for use in the particular application and the anatomical structure (e.g., respiratory tract, lung, reproductive tract and/or organ, urinary tract and organs, nasal passage, sinus, veins, artery, tunsile, tympanic membrane, or joints).

[0087] Now referring to FIG. 3 A, a portion of a HAS treating assembly 100 embodying features of the present invention is shown including an expander assembly 300. The expander assembly 300, such as balloon assembly 310 which includes an expandable expander member such as expander balloon 320, is disposed in an expanded configuration in a hollow anatomical structure such as the stomach 12. The expander balloon 320 is adapted for expanding within the interior of the HAS and conforming the interior of the stomach 12 to the shape and volume of the expanded expander member such that at least portions of the outer surface 325 of the expander balloon 320 are in surface contact with the inner wall 123 of the HAS.

[0088] An interior 330 of expander balloon 320 is in fluid communication with an inflation/deflation source (FIG. 6) through a conduit, such as lumen of an elongate body, such as catheter 400 (by way of example and not limitation, inflation deflation may be achieved through the same or different lumens). Expander balloon 320, as shown, is disposed at a distal end 403 of the catheter 400.

[0089] A distal portion 335 of the expander balloon 320 is shaped, upon expansion, to be similar to a portion of the HAS, preferably distal to the desired treatment site; such as the pyloric sphincter 22. In operation the shaped distal portion 335 is inflated and seats against the distal end of the pyloric sphincter.

[0090] Expander balloon 320 includes treatment areas 340 (shown as dotted pattern) corresponding to any one or more of desired target treatment sites of the HAS. In the case of the stomach, in the embodiment shown, the desired treatment sites are those of the stomach's and include any one or more areas corresponding to or in the vicinities of the greater curvature of the stomach, smaller curvature of the stomach, cardiac zone, gastric/fundic zone, pyloric zone, or the vagal nerve within the stomach, or the small intestine.

[0091] The balloon treatment areas 340 include magnetic regions 345 adapted for being sensed, directly or indirectly, by one or more magnetic sensors 902 or providing information as to the presence of the magnetic region to the magnetic sensor. The magnetic regions 345 comprise magnetic material 346 responsive to the magnetic sensor 902. The magnetic material may be formed above or beneath an exterior 326 (FIGS. 3 Al and 3 A2), be incorporated into the material forming the expander balloon, or be disposed in between layers 321 and 322 (FIG. 3 A3) of material forming the expander balloon as for example when the expander balloon is formed from multiple layers. The magnetic material may be deposited, sputtered, coated, painted or disposed on, about, or within the expander balloon, or by any other suitable means. The magnetic regions 345 may form a continuous region or multiple interrupted regions, extending circumferentially or longitudinally along at least a portion of the extender balloon. The shape of the magnetic regions may be uniform throughout or different regions may have different shapes and may be formed from the same or different materials. Inflation of expander balloon 320 expands the stomach to stretch the pleated mucosa of the stomach and expose underlying nerves and stomach muscle, and to bring into surface contact the treatment site with the magnetic regions. In an embodiment, the extender balloon is pre-shaped and upon expansion, expands and conforms the HAS to the expanded shape of the expander balloon.

[0092] The magnetic material may be formed from any one or more suitable materials.

Exemplary magnetic materials include, but are not limited to: ceramic, or ferrite, magnets; alnico magnets; ticonal magnets; composite magnets of various types of resin and magnetic powders. The magnetic material, preferably comprises a ferrous metal compounds.

[0093] Now referring to FIGs. 3A and 4A, the magnetic sensor 902 is disposed at a distal end 903 of an elongate member 900 of a sensor assembly 905. In an embodiment, the magnetic sensor 902 is disposed on, in, or about an expandable member 915 ("sensor balloon") disposed at the distal end of the sensor elongate member. The sensor elongate member preferably includes at least one lumen 920 (FIGs. 5AA and 5AB) extending along at least a distal portion thereof. The lumen 920 may be adapted to provide inflation/deflation fluid to and from the sensor balloon 915. In an embodiment, the expander balloon and its treatment sites may extend into the small intestine to provide treatment to at least a portion of the small intestine.

[0094] In an embodiment (FIG. 3A), the sensor balloon includes energy regions 1000 (FIG. 4A) which may include electrodes 1010 (FIGs. 4Cl - 4C4) disposed on or about sensor balloon 915. In operation, electrodes 1010 are adapted to provide ablative energy to the expander balloon 320 which is in surface contact with the inner surface 123 of the stomach. The electrodes are disposed in close proximity of the magnetic sensors 902. Electrodes 1010 and magnetic sensors 902, by way of leads (not shown) which may be independent of one another, are in communication with an energy source 580 and a processor which are normally associated with the external control assembly 500. It should be appreciated that the magnetic sensors and the energy regions, such as the electrodes, may be disposed on the same or separate structures which are associated with one another.

[0095] Upon expansion (e.g., inflation by way of an inflation fluid directed through a lumen of the sensor elongate member) of the sensor balloon, the sensor balloon 915 extends from a distal end of the sensor elongate member and is navigated inside the extender balloon 320. The sensor elongate member adapted for flexible movement is moved around the interior of expander balloon 320. As the sensors 902 are disposed at or in the near vicinity of the magnetic regions 345, the sensors sense the presence of the magnetic regions and transmit a signal to the processor. A signal is transmitted from the control assembly to the energy generator and the energy source transmits/provides energy to energy regions 1000 such as electrodes 1010. Electrodes 1010 being in surface contact (preferably non-penetrating) with the magnetic regions 345, transmit ablative energy to the expandable balloon 320 and the target treatment areas of the stomach. This enables guided delivery of ablative energy to the tissue or nerves at the desired target sites of the hollow anatomical structure.

[0096] Now referring to FIGs. 4B1-4B4 and 4C1-4C4, portions of exemplary sensor assembly 905 embodying features of the present invention are illustrated. As can be seen, the sensor member such as sensor balloon 915 may take various shapes, as for example, conical, circular, cylindrical, mushroom, etc. The electrodes 1010 may be disposed on, in, or about the sensor member in any suitable location and/or number. As can be appreciated by those skilled in the art, the shape of the sensor member and the shape, location, and number of electrodes may be adapted to suit a particular hollow anatomical structure and application.

[0097] As shown, a visualization device such as endoscope 950 is disposed within a lumen 920 (FIGs. 4AA, 4AB, 5AA, 5AB) of the sensor elongate member. In operation, sensor elongate member 900 and the preloaded endoscope 950 are advanced together into the stomach. Endoscope 950 may include illumination source such as lights (not shown) for visualization of the organ when it is disposed within the interior of the expander balloon.

[0098] In another embodiment, the source of energy is a hot fluid such as, but not limited to, hot water, hot saline, hot air, steam; and is controllable by the control assembly 500. In this configuration, the presence of electrodes is not necessary or is optional. In operation, sensor assembly is introduced into extender balloon. Upon introduction of hot fluid into an interior 925 of the sensor balloon forming at least in part a portion of the energy region 1000, the sensor balloon expands and extends out from the distal end of the sensor elongate member. With the sensor balloon extended out, the sensor assembly is navigated inside the extender balloon as described above. Energy is delivered from the sensor balloon to the expander balloon and the target tissue sites as described earlier. Similarly, a visualization device may be used in combination with the sensor assembly.

[0099] The temperature of the energy at its source is sufficiently high to provide a sufficiently high temperature at the point of treatment. The temperature of the energy, when in the form of fluid energy, at its source, in the case of treatment of the stomach, may range from about 60 to about 110°C, from about 70 to about 105°C, from about 75 to about 85°C. The temperature at the point of treatment is sufficiently high to effectuate the desired treatment. The temperature at the point of treatment, for the stomach, may range from about 50 to about 100°C, from about 60 to about 95°C, from about 60 to about 80°C.

[00100] One or more temperature sensors may be located in, on, or about the sensing balloon and/or the expander balloon. It should be appreciated that the sensor may take any appropriate form, as for example formed of wireless construction, and may further be configured to sense and convey the necessary information in any number of ways and formats and is not limited to direct sensors. In an embodiment, the temperature sensor is a thermocouple for sensing the temperature at the energy regions. By way of example and not limitation, the temperature may be sensed by optical means which can assess a change in the color of a portion of sensing balloon. In this configuration, colorants may be present in the material forming the sensing balloon or be painted or deposited on its material (on the inner or outer surface). Once the colored area is exposed to the elevated temperature, the colorant may change its characteristics. Information as to the temperature may then be conveyed to the practitioner. The information may be conveyed automatically by instrumentation or by direct visualization through the visualization device. Additionally or alternatively, such sensors may also be present on or in the organ expander member.

[00101] It should be appreciated that other configurations embodying features of the present invention are also contemplated. By way of example, the expander member may include electrodes or magnetic material closely associated with such electrodes which are responsive to magnetic sensors. Once the sensors of the sensor balloon are disposed at or in close proximity of these electrodes, an energy delivery circuit is completed, activating the electrodes for transmitting ablative energy to the tissue site.

[00102] In an embodiment, other sensing methods and apparatus may be used. By way of example, the expander member may include ultrasonic regions which differ in their properties from other portion of the expander member. The ultrasonic regions, similar to the magnetic regions, correspond to the target treatment sites of the anatomical structure. An ultrasonic sensor member, once disposed at or near the ultrasonic regions, enables the delivery of energy to energy regions, such as electrodes. Similarly, energy is delivered to the ultrasonic regions of the expander balloon and is transmitted to the desired target treatment sites of the anatomical structure.

[00103] In another embodiment, as shown in FIG. 3B, wherein like references refer to like elements, a HAS treatment assembly 100 may include a reference point positioner 700 disposable at a distal end 103 of the expander assembly 300. Preferably, reference point positioner 700 comprises a positioning balloon 703 adapted for inflation in the patient's body using means such as a conventional air or liquid tube 710 that may also acts as a catheter guide. In operation, positioning balloon 703 is inflated after passing through the pyloric sphincter 22 and seats against the distal side of the pyloric sphincter 22. Once seated, inflated positioning balloon 703 sets a reference point for tube 710 and allows proper positioning of the balloon assembly 310 without necessarily using a visualization apparatus.

[00104] Now referring to FIG. 5A, the expander assembly 300 of FIG. 3A is shown as part of a HAS treating assembly 100. The expander assembly 300 includes an elongate body such as catheter 400 (FIGs. 3A, 5AA) with proximal and distal ends, 406 and 403, respectively (FIG. 5A); and at least one lumen, such as lumen 410 extending along at least a distal portion thereof (FIG. 5AA). As shown in FIGs. 3 A and 5 A the expander balloon 320 is disposed at the distal end of the HAS catheter 400 and extends from a distal end 606 of the introducer 600. As shown in FIG. 5A and cross-sections 5AA and 5AB, the sensor assembly 903 is disposed within the expander catheter with the endoscope 950 disposed within the sensor. Endoscope (or other visualization tool) 950, during a procedure, may be extended into the interior 330 of the extender balloon 320 for better visualization of the treatment site. The expander assembly, sensor assembly, and endoscope are accessible through hand-piece 190 disposed at the proximal end 110 of the treatment assembly 100. For purposes of clarity in FIGs. 5AA and 5AB, only the overall structure of the introducer, catheter, sensor assembly, and/or endoscope are shown (e.g., the magnetic regions are not shown).

[00105] Now referring to FIG. 5B, wherein like references denote like elements, expander assembly of FIG. 3B is shown as part of a HAS treating assembly 100. A distal end 103 of HAS treating assembly 100 includes the reference point positioner 700 with the positioning balloon 703 adapted for inflation in the patient's body using the air or liquid tube 710 that also acts as a catheter guide.

[00106] The expander assembly 300 comprises, for example, the balloon assembly 310 integrated with the catheter 400 having a distal tip 420. In FIG. 5B balloon assembly 310 is collapsed. Catheter 400 allows balloon assembly 310 to be inserted into the patient's body over tube 710. Then, using an air line in handpiece 190 disposable at the proximal end 110 of the treating assembly 10, expander balloon 320 is inflated to expand the stomach's volume. The HAS expander assembly, the reference point positioner, and tube 710 (and the endoscope when present), as well as the sensor assembly and the visualization device, are accessible through hand-piece.

[00107] The magnetic sensors are configured for communication with the energy source 580. Energy source 580 is connectable by way of conduit 512 to energy generator 520 and is controllable by way of the control assembly 500. The amount and level of energy at its source is set to provide a sufficient level of energy at the point of treatment. The desired energy level differs for different hollow anatomical structures. The temperature at the point of treatment is sufficiently high to effectuate the desired treatment.

[00108] One or more temperature sensors may be located within or about the sensor balloon and/or the expander balloon. In an embodiment, the temperature sensor is a thermocouple or thermistor. The temperature sensor is coupled to a communication link (such as a conductor), which is coupled to a processor. For example, in the case where the temperature sensor is a thermocouple, the communication link may comprise a D/A converter coupled to a register disposed for reading by the processor. The processor reads a temperature sensor value from the temperature sensor and, responsive thereto, controls the signal generator so as to achieve delivery of an effective amount of energy to a desired section of tissue to be ablated. The processor thus uses the information from the signal generator, the information from the magnetic sensor, and temperature sensor, as a feedback loop for controlled delivery of energy to a section of the stomach (or other treatment areas of a hollow anatomical structure). For example, the processor may control the delivery of energy to achieve delivery of a selected amount of energy, a selected temperature, or a selected amount of ablation of a section of a stomach. A variety of positionings for the temperature sensors are possible.

[00109] As described above, the temperature or some other property of the tissue being ablated, or of the energy, can be monitored using a variety of sensors. By way of example, open and a closed loop feedback systems may be utilized for coupling a sensor used in the apparatus to an energy source so that the output energy of the energy source is adjusted in relation to the property sensed by the sensor. One or more sensors may be located within or about the expander member, at or about the magnetic regions, sensor balloon. It should be appreciated that the sensor may take any appropriate form, as for example formed of wireless construction, and may further be configured to sense and convey the necessary information in any number of ways and formats and is not limited to direct thermal sensors. By way of example and not limitation, the temperature may be sensed by optical means which can assess a change in the color of at least a portion of expander member (e.g., magnetic regions). In this configuration, colorants may be present in the material forming the expander member/regions or be painted or deposited on its material (on the inner or outer surface). Once the colored area is exposed to the elevated temperature, the colorant may change its characteristics. Information as to the temperature may then be conveyed to the practitioner. The information may be conveyed automatically by instrumentation or by direct visualization through the endoscopic device. As stated, such sensors may also be present on or in the expandable member.

[00110] Regardless of the configuration, HAS expander member 320 and/or the sensor member may be, independently, formed from any suitable material such as, but not limited to expandable, noncompliant (or semi-compliant) material including Mylar, Nylon, PET,

PeBax, IEBA. In a preferred embodiment, the material for balloons 320 is formed from non- compliant material. For example, Mylar, while expandable, is noncompliant and restricts expansion of the expander balloon within the stomach. Therefore, an expander balloon formed from Mylar cannot infinitely expand and patient injury resulting from unintended over-inflation of expander balloon can be reduced. In an embodiment, when used for obesity treatment, expander balloon is constructed such that when inflated within the stomach, the stomach expands from its empty volume (about 1 liter) to at least about twice the stomach's empty volume (e.g. 2 liters). However, for other hollow anatomical structures and other species, the expandable member may have different profiles or volumes. In an embodiment, the expander balloon is pre-shaped such that as the expander balloon is expanded within the hollow anatomical structure, the interior of the hollow anatomical structure conforms to the profile of the expander balloon.

[00111] Optional visual markings, corresponding to desired target areas of the HAS, may be located on the expander balloon. The visual markings are used to aid in locating the desired treatment target areas. Such visual markings may be incorporated into or deposited on or within the material forming the member. In an embodiment, the visual markings may take the form of colorant, metallic or polymeric material. Although some sort of visual marking may be preferred, the practitioner may identify the necessary areas for transfer of energy using practitioner's experience. The visual markings may be positioned to correspond to any one or more areas corresponding to or in the vicinities of the greater curvature of the stomach, smaller curvature of the stomach, cardiac zone, gastric/fundic zone, pyloric zone, or the vagal nerve within the stomach.

External Control

[00112] Now referring back to FIGs. 2 and 6, the external control portion 500 for apparatus 80 is shown and includes a control unit 510. Control unit 510 may include any one or more of the following subassemblies: treatment energy source 520 for providing and controlling energy source 580, controller 530, I/O device 540, inflation fluid delivery unit 250, and GUI 560.

[00113] Summarily, control unit 510 governs the power levels, cycles, and duration of energy transmitted through line 512 to the energy source and the energy regions to achieve and maintain temperature levels that achieve the treatment objectives. Foot switch 511 allows hands-free control of energy delivery. In tandem, control unit 510 controls delivery of processing (inflation) fluid and, if needed, the removal of aspirated material through fluid lines 555.

[00114] Controller 510 includes an Input/Output (I/O) device 540. The I/O device 540 allows practitioners to enter control and processing factors enabling control unit 510 to generate correct command signals. The I/O device 540 also receives real time processing feedback information from the one or more sensors associated with the sensor member, the expander member or the magnetic regions, as well as the endoscope when present (e.g., visualization data). The feedback information is processed by the controller 530, to govern energy application and processing inflation fluid as well as energy delivery. The I/O device 540 also includes a graphical user interface (GUI) 560 that graphically presents processing information to the practitioner for viewing and/or analysis. The energy may be in the form of electromagnetic energy (e.g., RF, microwave) and ultrasonic energy, infrared energy, visible laser energy, heat energy, or the like.

Therapeutic Procedure/Method

[00115] For purposes of discussion, exemplary therapeutic methods embodying features of the present invention will be described in the context of the treatment of the stomach. However, it should be noted that the methods of the present invention are equally applicable in the treatment of other hollow anatomical structures. It is contemplated and within the scope of the present invention to utilize variations such as those regarding the steps, components, visualization tools, introducers, and points of access to the anatomical structure may be modified as necessary. Because practitioners need not make any incisions (or in the case of transcutaneous or laparoscopic procedures the incision is minimal), and in far contrast to the complex and highly invasive bariatric surgeries currently practiced, the treatment according to the present invention is minimally invasive. In an embodiment, the procedure takes about one hour, including preparation and minimal recovery times. In an embodiment, patients can be treated on an out-patient basis using conscious sedation and since the risk of serious problems during the treatment is low it does not necessarily require the complete back-up of a hospital for emergencies.

[00116] In an embodiment for treatment of the gastric tract, and in operation, a gastric introducer is positioned in the patient's throat and protects the esophageal walls during the procedure.

[00117] The expander assembly, preloaded with the sensor assembly and the endoscope (when present) is inserted into patient's body through the introducer. The expander balloon is advanced distally positioning the shaped distal portion against the distal side of the pyloric sphincter. Using an inflation fluid line, such as an air line (e.g., extending along an inner lumen of catheter 400), through a hand-piece disposed at the proximal end of the HAS treatment assembly, the expander member is inflated until the stomach's volume reaches the desired volume, such as at least about twice its empty volume (e.g. to about 2 liters). The pre-shaped distal portion, at the expanded configuration, seats against the distal side of the pyloric sphincter, providing an anchor and aiding in position and placement of the expander assembly within stomach.

[00118] Once the expander member is expanded, the treatment regions including the magnetic regions are disposed at the desired target areas of the stomach (or other hollow anatomical structure).

[00119] The sensor balloon with the sensors is extended out from the distal end of the sensor elongate member. In an embodiment, the sensor balloon is extended from the distal end of the sensor elongate member upon being inflated with an inflation fluid (e.g., deliverable through the lumen of the sensor elongate member). With assistance of the endoscope, when present, the sensor balloon is navigated within the interior of the expander balloon. As the sensors are disposed at or in the near vicinity of the magnetic regions, the sensors sense the presence of the magnetic regions and transmit this information to the processor. A signal is transmitted from the control assembly to the energy generator and the energy source transmits/provides energy to energy regions such as the electrodes disposed on, in, or about the sensor balloon. The electrodes are brought (preferably non-penetrating) surface contact with the magnetic regions of the expander balloon which then transmit the ablative energy to the desired target treatment sites of the stomach.

[00120] In an embodiment, the treatment regions of the sensor balloon are the balloon itself. Energized fluid such as hot water, steam, saline, and the like is delivered into the sensor balloon. The sensor balloon extends out from the distal end of the sensor elongate member. The sensor balloon is navigated within the stomach. Upon sensing of the magnetic regions of the expander balloon, the sensor balloon (including the hot fluid) is brought into contact with the magnetic regions. Ablative energy is transferred from the magnetic regions to the desired target tissue sites of the stomach.

[00121] As stated earlier, the energy may be in the form of electromagnetic energy

(e.g., RF, microwave), ultrasonic energy, infrared energy, visible laser energy, heat energy, hot fluid or the like. During the treatment period, using GUI and feedback from

corresponding sensor associated with such magnetic regions, the practitioner can monitor the temperature at the site. The duration of time and frequency of applied energy are, of course, responsive to judgments of medical personnel.

[00122] After the practitioner is satisfied that the desired amount of tissue has been treated (for example ablated) and/or the pulse transmissions between nerves and the brain have been affected by the desired amount, energy application is stopped. The sensor balloon and the expander balloon are deflated, and the sensor assembly, expander assembly, and the endoscope are withdrawn from the patient, as is the gastro introducer.

[00123] In another embodiment embodying features of the present invention, after patient sedation, the reference point positioner (e.g., reference point balloon) is introduced into the patient's alimentary canal. The positioning balloon is advanced through the stomach and onto the distal side of the pyloric sphincter. The positioning balloon is inflated to seal against the distal side of the pyloric sphincter. This sets a fixed reference point for the tube. A gastric introducer positioned in the patient's throat, protects the esophageal walls during the next steps in the process. The expander assembly, sensor assembly, and the endoscope are introduced into the hollow anatomical structure. The desired target areas are treated as described above.

[00124] The extender assembly is now introduced into the patient's digestive system through the gastric introducer and by the catheter riding over tube. When distal tip of the catheter contacts the positioning balloon and the closed pyloric sphincter, the practitioner stops inserting the stomach expander into the patient. Balloon member is then inflated until the stomach's volume becomes about twice its empty volume.

[00125] The practitioner, using same or similar methodology as that described above treats the desired areas of the hollow anatomical structure. After the practitioner is satisfied that the desired target sites have been treated, energy application is stopped. The reference positioner, the expander balloon, and the sensor balloon are deflated and withdrawn long with the endoscope from the patient, as is the gastro introducer.

[00126] FIGS. 7A and 7B very schematically show the disruption and slowing of the travel of nerve pulses S, S' between the stomach 12, the small intestine 14, and the brain. In FIG. 5 A, smaller ablated portions Q of exemplary nerve 15 disrupt the straight flow of nerve signal impulses S between the stomach, small intestine, and brain. In FIG. 5B, larger ablated portions Q' of exemplary nerve 15 more greatly disrupt the straight flow of nerve signal impulses S' between the stomach, small intestine, and brain. The size of ablated portions Q, Q' and the desired degree of associated signal disruption are left to the sound judgment of the practitioner after considering, for example, the degree of patient's obesity, strength of patient's hunger sensations, and variation in nerve size from patient to patient.

[00127] FIG. 8 is an exemplary depiction of the appearance of the muscle profile of a treated stomach about 3 months post-op. There will now be major muscular constrictions and lesions (dead tissue) 121 in the areas of the fundus 25, peritoneum 30 and pylorus 23. These muscular constrictions and associated lesions should cause patient weight loss for the reasons discussed above. Because the procedure does not cause complete cell death in the treated areas, over long periods of time continued healing may cause the stomach's muscle profile to return to normal. Accordingly, follow-up treatments may be required. However, due to the process' simplicity, this should not pose any undue risk or inconvenience to the patient.

Conclusion

[00128] While this application describes certain exemplary embodiments of treatments for weight-based medical conditions and apparatus useful for carry out the treatments, only the attached claims define the scope of the invention.