US20230130437A1 - Systems and methods for treating tissue with radiofrequency energy - Google Patents

Abstract

A system for controlling operation of a radiofrequency treatment device to apply radiofrequency energy to tissue to heat tissue to create lesions without ablating the tissue. The system includes a first treatment device having at least one electrode for applying radiofrequency energy to tissue, a controller including a connector to which a first treatment device is coupled for use, and a generator for applying radiofrequency energy to the electrodes. The controller controls application of energy so that the tissue is thermally treated to create lesions but preventing thermal treatment beyond a threshold which would ablate the tissue.

Description

RELATED APPLICATIONS
• This application claims the benefit of Provisional Application Serial No. 61/664,960, filed Jun. 27, 2012 and is a continuation-in-part of Application Serial No. 12/924,155, filed Sep. 22, 2010 which claims the benefit of Provisional Application Serial No. 61/277,260 filed 22 Sep. 2009. The entire contents of each of these applications are incorporated herein by reference.
FIELD OF THE INVENTION
• In a general sense, the invention is directed to systems and methods for treating interior tissue regions of the body. More specifically, the invention is directed to systems and methods for treating dysfunction in body sphincters and adjoining tissue by applying radiofrequency energy to tissue to create tissue lesions without ablating tissue.
BACKGROUND OF THE INVENTION
• The gastrointestinal (GI) tract, also called the alimentary canal, is a long tube through which food is taken into the body and digested. The alimentary canal begins at the mouth, and includes the pharynx, esophagus, stomach, small and large intestines, and rectum. In human beings, this passage is about 30 feet (9 meters) long.
• Small, ring-like muscles, called sphincters, surround portions of the alimentary canal. In a healthy person, these muscles contract or tighten in a coordinated fashion during eating and the ensuing digestive process, to temporarily close off one region of the alimentary canal from another region of the alimentary canal.
• For example, a muscular ring called the lower esophageal sphincter (or LES) surrounds the opening between the esophagus and the stomach. Normally, the lower esophageal sphincter maintains a high-pressure zone between fifteen and thirty mm Hg above intragastric pressures inside the stomach.
• In the rectum, two muscular rings, called the internal and external sphincter muscles, normally keep fecal material from leaving the anal canal. The external sphincter muscle is a voluntary muscle, and the internal sphincter muscle is an involuntary muscle. Together, by voluntary and involuntary action, these muscles normally contract to keep fecal material in the anal canal.
• Dysfunction of a sphincter in the body can lead to internal damage or disease, discomfort, or otherwise adversely affect the quality of life. For example, if the lower esophageal sphincter fails to function properly, stomach acid may rise back into the esophagus. Heartburn or other disease symptoms, including damage to the esophagus, can occur. Gastrointestinal reflux disease (GERD) is a common disorder, characterized by spontaneous relaxation of the lower esophageal sphincter.
• Damage to the external or internal sphincter muscles in the rectum can cause these sphincters to dysfunction or otherwise lose their tone, such that they can no longer sustain the essential fecal holding action. Fecal incontinence results, as fecal material can descend through the anal canal without warning, stimulating the sudden urge to defecate. The physical effects of fecal incontinence (i.e., the loss of normal control of the bowels and gas, liquid, and solid stool leakage from the rectum at unexpected times) can also cause embarrassment, shame, and a loss of confidence, and can further lead to mental depression.
• In certain surgical systems, radiofrequency energy is applied to tissue at different tissue levels to create multiple tissue lesions. Application of such energy requires continuous monitoring of certain tissue and/or device parameters to ensure that the tissue is not heated to such extent that damaging burning of tissue occurs. Thus, these systems monitor tissue temperature and/or device electrode temperature and provide safety features to cut off energy flow if the tissue temperature rises too high. However, with the application of radiofrequency energy, there is a fine point in which tissue is treated to form lesions and beneficially alter structure of the tissue, e.g., alter the structure of the sphincter muscle, while not being ablated or burned.
• Ablation of tissue can be generally defined as a removal of a part of tissue. Radiofrequency energy to ablate tissue has been used for various tumor treatments, destroying tissue and creating tissue necrosis. However, avoiding tissue ablation may be beneficial in treating the gastrointestinal tract in the foregoing or other procedures. Therefore, it would be advantageous to provide a system of applying radiofrequency energy to tissue at a power setting and time duration which causes thermal effect to tissue to create tissue lesions along a series of tissue levels but avoids ablation or burning of tissue.
• However, in avoiding tissue ablation, care needs to be taken to ensure that tissue is not undertreated. In other words, in attempts to prevent overheating of tissue which causes ablation, the system needs to conversely ensure that tissue is not under-heated and thus not therapeutically treated. Therefore, the need exists for a system that applies radiofrequency energy to tissue between these two energy levels.
SUMMARY OF THE INVENTION
• The present invention advantageously provides an electrosurgical system that applies radiofrequency energy to tissue to create tissue lesions at different tissue levels and alters the structure of the tissue, e.g., the sphincter muscle, without ablating or burning the tissue, while on the other hand reducing the incidence of tissue undertreatment. This is achieved in one aspect by accurate calibration of the tissue temperature measurement mechanism and improvement of appropriate reading and response to high tissue temperatures. This is achieved in another aspect by improved application of cooling fluid to the tissue during the surgical procedure to provide quick response to rising tissue temperatures. This is achieved in still another aspect by placement of data collection hardware in the treatment device, closer to the source. This is achieved in yet another aspect by providing a visual warning to the user of too high a temperature as soon as the needle electrodes are deployed before energy is applied. In yet another aspect, accurate spacing of tissue level treatments is achieved to reduce overlapping of energy application.
• Moreover, the present invention advantageously provides such electrosurgical system that avoids such overheating of tissue, while at the same time limiting under-heating of tissue which does not effectively treat tissue. Thus, in striking this balance between the overheating and under heating of tissue, more reliable and consistent tissue treatment is achieved.
• This prevention of undertreatment is achieved in various ways, all designed to avoid disabling/cut off of energy to the electrodes if such cutoff is not warranted. In one aspect, avoidance of undertreatment is achieved by more accurate temperature reading due to placement of the data collecting hardware in the surgical treatment device and shielding the hardware, thereby reducing susceptibility to noise which can disrupt communication and reporting this collected data to the controller/generator. In another aspect, a multiple checking of errors confirms that energy cutoff is really warranted.
• The foregoing different aspects utilized to achieve the desired tissue treatment can be implemented alone or in combination with each other.
• Thus, the system and method of the present invention advantageously keeps tissue treatment within a target zone to provide a therapeutic effect to tissue, defined as thermally heating tissue above a lower parameter wherein tissue is undetreated and below a tissue ablation threshold wherein tissue is overheated and ablated.
• In one embodiment of the present invention a system for controlling operation of a radiofrequency treatment device to apply radiofrequency energy to tissue to heat tissue to create tissue lesions without ablating the tissue is provided. The system includes a first treatment device having at least one electrode for applying radiofrequency energy to tissue, a controller including a connector to which a first treatment device is coupled for use, and a generator for applying radiofrequency energy to the electrodes. The controller controls application of energy so that the tissue is thermally treated to create lesions but prevents thermal treatment beyond a threshold which would ablate the tissue. The controller can further include an operation system to execute on a display screen a first graphical interface guiding use of the first treatment device, the controller visually prompting a user in a step-wise fashion to perform a process using the connected treatment device of forming a pattern of lesions in a body region in a plurality of axially spaced lesion levels, each lesion level including a plurality of circumferential spaced lesions.
• In some embodiments, the treatment device includes a handle and a shielded printed circuit board contained in the handle, the printed circuit board enabling precise measurement of tissue and electrode parameters to regulate tissue temperature to prevent thermal treatment of tissue beyond the threshold, and the shield reducing interference.
• In some embodiments, the controller automatically increases the flow of cooling fluid to the tissue if a tissue temperature exceeds a predetermined value to thereby reduce the tissue temperature to prevent thermal treatment of tissue beyond the threshold.
• In some embodiments, the printed circuit board is calibrated in manufacture to improve the temperature accuracy to prevent thermal treatment of tissue beyond the threshold.
• In another embodiment, the present invention provides a method of treating fecal incontinence comprising the steps of:
• providing a treatment device having a plurality of electrodes;
• applying radiofrequency energy to the electrodes to thermally treat tissue below a tissue ablation threshold and create a plurality of tissue lesions along axially spaced tissue levels within the anal canal;
• monitoring tissue temperature throughout the procedure; and
• regulating power ensuring in response to the monitoring step that the tissue temperature does not exceed a predetermined value which would cause tissue ablation and/or tissue necrosis.
• In some embodiments, the ensuring step is achieved by providing an automatic cooling system to apply cooling fluid to the tissue if a measured temperature exceeds a predetermined value.
• In some embodiments, the ensuring step is achieved by placement of a printed circuit board in a handle of the treatment device so tissue temperature monitoring occurs closer to the target tissue to thereby improve accuracy of temperature reading.
• In some embodiments, the ensuring step is achieved by placement of a printed circuit board adjacent to and external of a handle of the treatment device so tissue temperature monitoring occurs closer to target tissue to thereby improve the accuracy of temperature reading.
• In some embodiments, the printed circuit board is calibrated in manufacture to improve the accuracy of the temperature reading.
• In another embodiment, the present invention provides a method of treating gastrointestinal reflux disease comprising the steps of:
• providing a treatment device having a plurality of electrodes;
• applying radiofrequency energy to the electrodes to thermally treat tissue below a tissue ablation threshold and create a plurality of tissue lesions along axially spaced tissue levels within the upper gastrointestinal tract;
• monitoring tissue temperature throughout the procedure; and
• regulating power ensuring in response to the monitoring step that the tissue temperature does not exceed a predetermined value which would cause tissue ablation and/or tissue necrosis.
• In some embodiments, the ensuring step is achieved by providing an automatic cooling system to apply cooling fluid to the tissue if a measured temperature exceeds a predetermined value.
• In some embodiments, the ensuring step is achieved by placement of a printed circuit board in a handle of the treatment device so tissue temperature monitoring occurs closer to target tissue to thereby improve the accuracy of temperature reading.
• In some embodiments, the ensuring step is achieved by placement of a printed circuit board adjacent to and external of a handle of the treatment device so temperature monitoring occurs closer to target tissue to thereby improve the accuracy of temperature reading.
• In some embodiments, the printed circuit board is calibrated in manufacture to increase accuracy of the temperature reading.
• The present invention also provides in another aspect a method of a treating tissue by applying non-ablative radiofrequency energy comprising the steps of
• providing an instrument with a plurality of electrodes;
• placing the electrodes near a sphincter to be treated; and
• applying through the electrodes radiofrequency energy which is a) sufficient to increase the smooth muscle to connective tissue without changes to the collagen I/III ratio to thereby remodel the sphincter but b) insufficient to ablate the tissue.
• In some embodiments, the application of radiofrequency energy reinforces the sphincter.
• In some embodiments, the step of providing the electrodes near the sphincter provides the electrodes near the internal anal sphincter.
• The present invention also provides in another aspect a system for controlling operation of a radiofrequency treatment device to apply radiofrequency energy to tissue to heat tissue to create lesions at a treatment range defined between under heating tissue to fail to achieve a therapeutic affect and overheating tissue to cause tissue ablation. The system comprises a controller including a connector to which a first treatment device having a plurality of electrodes for applying radiofrequency energy to tissue is coupled for use, and a generator for applying radiofrequency energy to the electrodes. The improvement comprises a multiple error checking system which if an error is detected which indicates disabling of an electrode of the treatment device, the system checks for a repeat of the error and determines if disabling is warranted or energy application is warranted to thereby reduce the likelihood of under treatment of tissue.
• In some embodiments, the multiple error checking system repeats the error check three times.
• The present invention also provides in another aspect a system for controlling operation of a radiofrequency treatment device to apply radiofrequency energy to tissue to heat tissue to create tissue lesions at a treatment range defined between overheating tissue to cause ablation and under heating tissue to fail to achieve a therapeutic effect. The system comprises a controller including a connector to which a first treatment device having a plurality of electrodes for applying radiofrequency energy to tissue is coupled for use, and a generator for applying radiofrequency energy to the electrodes. The controller controls application of energy so that the tissue is thermally treated to create tissue lesions but prevents thermal treatment beyond a threshold which would ablate the tissue. The system further includes a cut off feature to cut off energy flow to disable an electrode if one of multiple potential errors is detected, the system further containing a feature to prevent premature disabling of an electrode.
• In some embodiments, the feature to prevent premature disabling of an electrode comprises a multiple error check in which if an error is detected, a measurement is rechecked to determine if the error is still present before cut off of energy flow.
• In some embodiments, the system further comprises an automatic pump system to increase the flow of cooling fluid if measured temperature exceeds a predetermined value.
• In some embodiments, the system further comprises an operation system to execute on a display screen a first graphical interface guiding use of the first treatment device coupled to the controller, the controller visually prompting a user in a step-wise fashion to perform a process using the couple treatment device of forming a pattern of lesions in a body region in a plurality of axially spaced lesion levels, each lesion level including a plurality of circumferential spaced lesions
• In some embodiments of such systems and methods, a graphical display is provided for visually prompting a user in a step-wise fashion to use a treatment device to perform a process of forming a pattern of lesions in a body region comprising a plurality of axially spaced lesion levels, each lesion level comprising a plurality of circumferential spaced lesions. The systems and methods include registering the formation of lesions as they are generated in real time, both within and between each circumferentially spaced level, whereby the graphical display displays for the user a visual record of the progress of the process from start to finish and guides the user so that individual lesions desired within a given level are all formed, and that a given level of lesions is not skipped.
• In some embodiments, the systems and methods include generating at each lesion level a first stylized graphical image with a number identification of its level, and generating a second stylized graphical image, different from the first stylized graphical image, generated when the formation of lesions at a given level is indicated and further showing the number of lesions to be formed at that level. The systems and methods include changing the second graphical image to a third graphical image, different than the first or second images, including added indicia to reflect the formation of lesions in real time. The systems and methods may further include generating a marker that directs the user to the next lesion level to be treated and that is updated as successive lesion levels are treated.
• Further features and advantages of the inventions are set forth in the following Description and Drawings, as well as in the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
• FIG.1 is a diagrammatic view of a unified system usable in association with a family of different treatment devices for treating body sphincters and adjoining tissue regions in different regions of the body.
• FIG.2 is a perspective view, with portions broken away, of one type of treatment device usable in association with the system shown inFIG.1 to treat tissue in the upper gastro-intestinal tract, the treatment device having an operative element for contacting tissue shown in a collapsed condition.
• FIG.2A is a perspective view of an alternate embodiment of the treatment device ofFIG.2.
• FIG.2B is a perspective view of another alternate embodiment of the treatment device ofFIG.2.
• FIG.3 is a perspective view, with portions broken away, of the device shown inFIG.2, with the operative element shown in an expanded condition.
• FIG.4 is a perspective view, with portions broken away, of the device shown inFIG.2, with the operative element shown in an expanded condition and the electrodes extended for use.
• FIG.5 is a lesion pattern that can be formed by manipulating the device shownFIGS.2 to4 in the esophagus at or near the lower esophageal sphincter and in the cardia of the stomach, comprising a plurality of axially spaced lesion levels, each lesion level comprising a plurality of circumferential spaced lesions.
• FIG.6 is a perspective view of another type of treatment device usable in association with the system shown inFIG.1 to treat tissue in the lower gastrointestinal tract, the treatment device having an array of electrodes shown in a retracted position.
• FIG.6A is a perspective view of an alternate embodiment of the treatment device ofFIG.6.
• FIG.6B is a perspective view of another alternate embodiment of the treatment device ofFIG.6.
• FIG.7 is a perspective view of the device shown inFIG.6, with the array of electrodes shown in their extended position.
• FIG.8 is a perspective view of the device shown inFIGS.6 and7, with the array of electrodes shown in their extended position deployed in the lower gastrointestinal tract to treat sphincter dysfunction in the anal canal.
• FIG.9 is a lesion pattern that can be formed by manipulating the device as shownFIG.8 in the anal canal at or near the anal sphincter, comprising a plurality of axially spaced lesion levels, each lesion level comprising a plurality of circumferential spaced lesions.
• FIGS.10A and10B are, respectively, left and right perspective views of one embodiment of an integrated device incorporating features of the system shown inFIG.1 and usable with either treatment device shown inFIGS.2 or6 for treating body sphincters and adjoining tissue regions, and also having a controller and a graphical user display for visually prompting a user in a step-wise fashion to use a treatment device to perform a process of forming a pattern of lesions in a body region like that shown inFIGS.5 or9, to guide the user so that individual lesions desired within a given level are all formed, and that a given level of lesions is not skipped.
• FIG.11 is a representative graphical user set-up display generated by the controller prompting the user with numbers and/or text and/or icons through the set-up and connection steps prior to a treatment procedure.
• FIG.12 is a representative graphical user set-up display generated by the controller upon identifying the connection of a device like that shown inFIGS.2 to4 (identified by the trademark STRETTA®).
• FIG.13 is a representative graphical user set-up display generated by the controller upon identifying the connection of a device like that shown inFIGS.6 to8 (identified by the trademark SECCA®).
• FIGS.14-A to14-Oare representative graphical user treatment displays generated by the controller for visually prompting a user to use a treatment device like that shown inFIGS.2 to4 in a step-wise fashion to perform a process of forming a pattern of lesions in an esophagus like that shown inFIG.5, the graphical user display guiding the user and creating a visual record of the progress of the process from start to finish, so that individual lesions desired within a given level are all formed, and that a given level of lesions is not skipped.
• FIG.14P illustrates graphical user displays relating to balloon inflation of the device ofFIG.3.
• FIG.14Q illustrates the display of balloon inflation icon ofFIG.14P
• FIGS.15A to15I are representative graphical user treatment displays generated by the controller for visually prompting a user to use a treatment device like that shown inFIGS.6 to8 in a step-wise fashion to perform a process of forming a pattern of lesions in an anal canal like that shown inFIG.9, the graphical user display guiding the user and creating a visual record of the progress of the process from start to finish, so that individual lesions desired within a given level are all formed, and that a given level of lesions is not skipped.
• The invention may be embodied in several forms without departing from its spirit or essential characteristics. The scope of the invention is defined in the appended claims, rather than in the specific description preceding them. All embodiments that fall within the meaning and range of equivalency of the claims are therefore intended to be embraced by the claims.
DESCRIPTION OF PREFERRED EMBODIMENTS
• This Specification discloses various systems and methods for treating dysfunction of sphincters and adjoining tissue regions in the body. The systems and methods are particularly well suited for treating these dysfunctions in the upper and lower gastrointestinal tract, e.g., gastro-esophageal reflux disease (GERD) affecting the lower esophageal sphincter and adjacent cardia of the stomach, or fecal incontinence affecting the internal and external sphincters of the anal canal. For this reason, the systems and methods will be described in this context. Still, it should be appreciated that the disclosed systems and methods are applicable for use in treating other dysfunctions elsewhere in the body, and dysfunctions that are not necessarily sphincter-related. For example, the various aspects of the invention have application in procedures requiring treatment of hemorrhoids, or urinary incontinence, or restoring compliance to or otherwise tightening interior tissue or muscle regions. The systems and methods that embody features of the invention are also adaptable for use with systems and surgical techniques that are catheter-based and not necessarily catheter-based.
• The systems and methods disclosed herein provide application of radiofrequency energy to tissue via a plurality of electrodes. The energy is applied via the electrodes to tissue at a series of axially spaced tissue levels, thereby forming tissue lesions which alters the tissue structure. Prior application of radiofrequency energy to tissue in various surgical procedures involved application of energy at certain levels and for a certain period of time with the goal to ablate the tissue. That is, the objective was to cause tissue necrosis and remove tissue. The systems and methods of the present disclosure, however, treat tissue without ablating the tissue and without causing tissue necrosis, which advantageously achieves better clinical results, especially when treating the sphincter muscles of the GI tract in the specific surgical procedures disclosed herein. By applying sufficient energy to cause thermal effect to tissue, but without ablating or burning the tissue, tissue reconstruction/remodeling occurs which results in beneficial changes to tissue properties, thus beneficially treating GERD which is caused by the spontaneous relaxation of the lower esophageal sphincter and beneficially treating fecal incontinence caused by loss of tone of the sphincter muscles in the anal canal. The system of the present disclosure rejuvenates muscle to improve muscle function. The system of the present invention also increases the smooth muscle/connective ratio which results in sphincter reinforcement and remodeling.
• In studies performed, it was found that application of non-ablative RF energy to sphincter muscle influences the structural arrangement of smooth muscle and connective tissue contents. The increase of the smooth muscle fibers area per muscle bundles as well as the collagen and myofibroblast contents within the internal anal sphincter were found to be potentially responsible for sphincter reinforcement and remodeling. More specifically, in studies, it was found that application on non-ablative RF energy increased smooth muscle/connective tissue ratio without changes (increase) in the collage I/III ratio. There was an increase in diameter and number of type I fibers in the external anal sphincter after non-ablative RF and higher cellular smooth muscle content in the internal anal sphincter, suggesting that sphincter remodeling by non-ablative RF energy resulted from activation and repopulation of smooth muscle cells, possibly related to phenotype switch of fibroblasts into myofibroblasts and external anal sphincter fibers. In one animal study, quantitative image analysis showed the cross-section occupied by smooth muscle within the circular muscle increased by up to 16& after non-ablative RF, without increase in collagen I/III ratio, and external anal sphincter muscle fiber type composition showed an increase in type I/III fiber ratio from 26.2% to 34.6% after non-ablative RF, as well as a 20% increase in fiber I type diameter compared to controls.
• For such aforedescribed non-ablation RF treatment, the system and method of the present disclosure also is designed to enhance lesion creation by avoiding unnecessary cutoff energy flow to electrodes in response to a perceived error.
• Various features of the controller and/or surgical treatment devices connected to the controller achieve the foregoing. Preventing overheating of tissue is achieved by enhanced temperature control of the tissue, which is accomplished in one way by more accurate temperature measurement so proper power adjustments can be made to address rising temperatures and accomplished in another way by enhanced application of cooling fluid.
• Preventing undertreatment of tissue is achieved in one way by location of the data collecting hardware closer to the source and achieved in another way by ensuring error detection does not lead to premature cutoff of energy flow. Each of these are ways are described in detail below.
I. Overview of the System
• FIG.1 shows aunified system24 for diagnosing and/or treating dysfunction of sphincters and adjoining tissue in different regions of the body. In the illustrated embodiment, thesystem24 is configured to diagnose and treat dysfunction in at least two distinct sphincter regions within the body.
• The targeted sphincter regions can vary. In the illustrated embodiment, one region comprises the upper gastro-intestinal tract, e.g., the lower esophageal sphincter and adjacent cardia of the stomach. The second region comprises the lower gastrointestinal tract, e.g., in the intestines, rectum and anal canal.
• Thesystem24 includes a family oftreatment devices26a and26b. Eachdevice26a and26b can be specifically configured according to the physiology and anatomy of the particular sphincter region which it is intended to treat. The details of construction of eachdevice26a and26b will be generally described later.
• Each device26a/26b carries anoperative element36a and36b. Theoperative element36a and36b can be differently configured according to the physiology and anatomy of the particular sphincter region which it is intended to treated. Still, if the anatomy and physiology of the two treatment regions are the same or similar enough, the configuration of theoperative elements36a and36b can be same or essentially the same.
• In the illustrated embodiment, theoperative elements36a and36b function in thesystem10 to apply energy in a selective fashion to tissue in or adjoining the targeted sphincter region. The applied energy creates one or more lesions, or a prescribed pattern of lesions, below the surface of the targeted region without ablating tissue. The subsurface lesions are desirably formed in a manner that preserves and protects the surface against thermal damage.
• Natural healing of the subsurface lesions leads to a reconstruction/remodeling of the tissue which leads to beneficial changes in properties of the targeted tissue. The subsurface lesions can also result in the interruption of aberrant electrical pathways that may cause spontaneous sphincter relaxation. In any event, the treatment can restore normal closure function to thesphincter region18 as the non-ablating application of radiofrequency energy beneficially changes the properties of the sphincter muscle wall. Such energy rejuvenates the muscle to improve muscle function.
• Thesystem24 includes agenerator38 to supply the treatment energy to theoperative element36a/36b of the device26a/26b selected for use. In the illustrated embodiment, thegenerator38 supplies radio frequency energy, e.g., having a frequency in the range of about 400 kHz to about 10 mHz. Of course, other forms of energy can be applied, e.g., coherent or incoherent light; heated or cooled fluid; resistive heating; microwave; ultrasound; a tissue ablation fluid; or cryogenic fluid.
• A selected device26a/26b can be individually coupled to thegenerator38 via acable10 to convey the generated energy to the respectiveoperative element36a/36b.
• Thesystem24 preferably also includes certain auxiliary processing equipment. In the illustrated embodiment, the processing equipment comprises an externalfluid delivery apparatus44 and anexternal aspirating apparatus46.
• A selected device26a/26b can be connected viatubing12 to thefluid delivery apparatus44, to convey processing fluid for discharge by or near theoperative element36a/36b. A selected device26a/26b can also be connected viatubing14 to the aspiratingapparatus46, to convey aspirated material from or near from theoperative element36a/36b for discharge.
• Thesystem24 also includes acontroller52. Thecontroller52, which preferably includes a central processing unit (CPU), is linked to thegenerator38, thefluid delivery apparatus44, and the aspiratingapparatus46. Alternatively, the aspiratingapparatus46 can comprise a conventional vacuum source typically present in a physician’s suite, which operates continuously, independent of thecontroller52.
• Thecontroller52 governs the power levels, cycles, and duration that the radio frequency energy is distributed to the particularoperative element36a/36b, to achieve and maintain power levels appropriate to achieve the desired treatment objectives. In tandem, thecontroller52 also desirably governs the delivery of processing fluid and, if desired, the removal of aspirated material. Thus, the controller maintains the target tissue temperature to ensure the tissue is not overheated.
• Thecontroller52 includes an input/output (I/O)device54. The I/O device54 allows the physician to input control and processing variables, to enable the controller to generate appropriate command signals. The I/O device54 also receives real time processing feedback information from one or more sensors associated with the operative element (as will be described later), for processing by thecontroller52, e.g., to govern the application of energy and the delivery of processing fluid.
• The I/O device54 also includes a graphical user interface (GUI), to graphically present processing information to the physician for viewing or analysis. Further details regarding the GUI will be provided later.
II. the Treatment Devices
• The structure of theoperative element36 can vary. Various representative embodiments will be described.
A. For Treatment of Upper Gastro-Intestinal Tract
• FIGS.2 to4 show a catheter-based device26a for treating sphincter regions in the upper gastro-intestinal tract, and more particularly, the lower esophageal sphincter and adjoining cardia of the stomach to treat GERD. In the embodiment shown, the device26a includes aflexible catheter tube30 that carries ahandle28 at its proximal end. The distal end of thecatheter tube30 carries theoperative element36a.
• In the illustrated embodiment, theoperative element36a comprises a three-dimensional basket56. Thebasket56 includes one ormore spines58, and typically includes from four to eightspines58, which are assembled together by adistal hub60 and aproximal base62. In the illustrated embodiment, fourspines58 are shown, spaced circumferentially at 90-degree intervals.
• In the illustrated embodiment, anexpandable structure72 comprising a balloon is located within thebasket56. Theballoon structure72 can be made, e.g., from a Polyethylene Terephthalate (PET) material, or a polyamide (non-compliant) material, or a radiation cross-linked polyethylene (semi-compliant) material, or a latex material, or a silicone material, or a C-Flex (highly compliant) material.
• Theballoon structure72 presents a normally, generally collapsed condition, asFIG.2 shows. In this condition, thebasket56 is also normally collapsed about theballoon structure72, presenting a low profile for deployment into the esophagus.
• Acatheter tube30 includes an interior lumen, which communicates with the interior of theballoon structure72. A fitting76 (e.g., a syringe-activated check valve) is carried by thehandle28. The fitting76 communicates with the lumen. The fitting76 couples the lumen to a syringe78 (seeFIG.3). Thesyringe78 injects fluid under pressure through the lumen into theballoon structure72, causing its expansion.
• Expansion of theballoon structure72 urges thebasket56 to open and expand (seeFIG.3). The force exerted by theballoon structure72, when expanded, is sufficient to exert an opening or dilating force upon the tissue surrounding the basket56 (seeFIG.31). The balloon can be expanded to varying diameters to accommodate for varying patient anatomy.
• Eachspine58 carries an electrode66 (seeFIG.4). Therefore, there are four electrodes circumferentially spaced at 90-degree intervals. In the illustrated embodiment, eachelectrode66 is carried within thetubular spine58 for sliding movement. Eachelectrode66 slides from a retracted position, withdrawn in the spine58 (shown inFIG.3) and an extended position, extending outward from the spine58 (seeFIG.4) through a hole in thespine58. A push-pull lever68 on thehandle28 is coupled by one or more interior wires to the slidingelectrodes66. Thelever68 controls movement of the electrodes between the retracted position (by pulling rearward on the lever68) and the extended position (by pushing forward on the lever68).
• Theelectrodes66 have sufficient distal sharpness and strength, when extended, to penetrate a desired depth into tissue the smooth muscle of the loweresophageal sphincter18 or the cardia of the stomach16 (seeFIG.32). The desired depth can range from about 4 mm to about 5 mm.
• Theelectrodes66 are formed of material that conducts radio frequency energy, e.g., nickel titanium, stainless steel, e.g.,304 stainless steel, or a combination of nickel titanium and stainless steel.
• In the illustrated embodiment (seeFIG.4), an electrical insulatingmaterial70 is coated about the proximal end of eachelectrode66. When the distal end of theelectrode66 penetrating the smooth muscle of theesophageal sphincter18 or cardia20 transmits radio frequency energy, thematerial70 insulates the mucosal surface of theesophagus10 or cardia20 from direct exposure to the radio frequency energy. Thermal damage to the mucosal surface is thereby avoided. The mucosal surface can also be actively cooled during application of radio frequency energy, to further protect the mucosal surface from thermal damage.
• In the illustrated embodiment (seeFIG.4), at least onetemperature sensor80 is associated with each electrode. Onetemperature sensor80 senses temperature conditions near the exposed distal end of theelectrode66, asecond temperature sensor80 is located on the correspondingspine58, which rests against the mucosal surface when theballoon structure72 is inflated.
• The externalfluid delivery apparatus44 is coupled via tubing12 (seeFIG.1) to connector48 (seeFIG.4), to supply cooling liquid to the targeted tissue, e.g., through holes in the spines. Theexternal aspirating apparatus46 is coupled via tubing14 (seeFIG.1) to connector50 (seeFIG.4), to convey liquid from the targeted tissue site, e.g., through other holes in the spine or elsewhere on thebasket56. Thecontroller52 can govern the delivery of processing fluid and, if desired, the removal of aspirated material.
• Thecontroller52 can condition theelectrodes66 to operate in a monopolar mode. In this mode, eachelectrode66 serves as a transmitter of energy, and an indifferent patch electrode (described later) serves as a common return for allelectrodes66. Alternatively, thecontroller52 can condition theelectrodes66 to operate in a bipolar mode. In this mode, one of the electrodes comprises the transmitter and another electrode comprises the return for the transmitted energy. The bipolar electrode pairs can includeelectrodes66 on adjacent spines, orelectrodes66 spaced more widely apart on different spines.
• In use, the device26a is manipulated to create a preferred pattern of multiple lesions comprising circumferential rings of lesions at several axially spaced-apart levels (about 5 mm apart), each level comprising from 8 to 12 lesions. A representative embodiment of the lesion pattern is shown inFIG.5. AsFIG.5 shows, the rings are preferably formed in the esophagus in regions above the stomach, at or near the lower esophageal sphincter, and/or in the cardia of the stomach. The rings in the cardia are concentrically spaced about the opening funnel of the cardia. At or near the lower esophageal sphincter, the rings are axially spaced along the esophagus.
• Multiple lesion patterns can be created by successive extension and retraction of theelectrodes66, accompanied by rotation and/or axial movement of the catheter tube to reposition thebasket56. The physician can create a given ring pattern by expanding theballoon structure72 and extending theelectrodes66 at the targeted treatment site, to form a first set of four lesions. The physician can then withdraw theelectrodes66, collapse theballoon structure72, and rotate thecatheter tube30 by a desired amount, e.g., 30-degrees or 45-degrees, depending upon the number of total lesions desired within 360-degrees. The physician can then again expand thestructure72 and again extend theelectrodes66, to achieve a second set of four lesions. The physician repeats this sequence until a desired number of lesions within the 360-degree extent of the ring is formed. Additional lesions can be created at different levels by advancing the operative element axially, gauging the ring separation by external markings on the catheter tube.
• As shown inFIG.5, a desirable pattern comprises an axially spaced pattern of six circumferential lesions numberedLevel 1 toLevel 6 in an inferior direction, with some layers in the cardia of the stomach, and others in the esophagus above the stomach at or near the lower esophageal sphincter. In the embodiment shown in instantFIG.5, in theLevels 1, 2, 3, and 4, there are eight lesions circumferentially spaced 45-degrees apart (i.e., a first application of energy, followed by a 45-degree rotation of thebasket56, followed by a second application of energy). In theLevels 5 and 6, there are twelve lesions circumferentially spaced 30-degrees apart (i.e., a first application of energy, followed by a 30-degree rotation of thebasket56, followed by a second application of energy, followed by a 30-degree rotation of thebasket56, followed by a third application of energy). InLevel 5, theballoon structure72 is only partially expanded, whereas inLevel 6, theballoon structure72 is more fully expanded, to provide lesion patterns that increase in circumference according to the funnel-shaped space available in the funnel of the cardia.
• Note that to secure against overinflation of the balloon, especially in tissue Levels 1-4 where the device is positioned in the esophagus, a pressure relief valve is attached to the air syringe, upstream of the balloon inflation port of the device, to allow air to escape if pressure levels are exceeded. That is, in Levels 1-4, the air syringe is filled with air, and the balloon is inflated to a target pressure so there is enough contact to slightly tension the tissue but not enough to stretch the tissue, with the pressure relief ensuring the pressure is not exceeded. Preferably, the balloon would be inflated to no more than about 2.5 psi. In the stomach, atLevels 5 and 6, there is more room for the balloon inflation, so the balloon can be further inflated and the pressure relief valve can be removed. The balloon is preferably inflated by volume to about 25 ml for treatment atLevel 5, and after treatment atLevel 5, deflated atLevel 6 to about 22 ml. Note atLevels 5 and/or 6, the inflated balloon can also be used as an anchor. In an alternate embodiment, after treatment ofLevel 4 the balloon is deflated and the instrument is advanced, then retracted, whereinLevel 6 is treated, then the instrument is pulled further proximally to subsequently treatLevel 5. Stated another way,Level 5 can be considered distal ofLevel 6 and therefore being more distal, treated beforeLevel 6. Note the balloon would still be inflated to about 25 ml in the more distal level and to about 22 ml in this embodiment. The balloon can also serve as an anchor.
• In an alternate embodiment of the treatment device26a, one or more digital cameras can be mounted along the catheter tube, e.g., with the camera lens directed to thebasket56, to provide visualization of the site. In another alternate embodiment, the catheter tube can be designed to fit within a lumen of an endoscope, relying on the endoscope for visualization of the site.
B. For Treatment of Lower Gastro-Intestinal Tract
• FIGS.6 and7 show a representative embodiment fordevice26b, which takes the form of a hand manipulateddevice302 for treating sphincter regions in the lower gastro-intestinal tract, and more particularly, the internal and/or external sphincter muscles in the anal canal to treat fecal incontinence. Thedevice302 includes ahand grip304 that carries theoperative element36b.
• In the illustrated embodiment, theoperative element36b takes the form of a hollow,tubular barrel306 made from a transparent, molded plastic material. Thebarrel306 terminates with a blunt, roundeddistal end308 to aid passage of thebarrel306 through the anal canal, without need for a separate introducer. Thehand grip304 includes aviewing port312 for looking into the transparent, hollow interior of thebarrel306, to visualize surrounding tissue.
• An array ofneedle electrodes316 are movably contained in a side-by-side relationship along an arcuate segment of thebarrel306. In the illustrated embodiment, theneedle electrodes316 occupy an arc of about 67.5 degrees on thebarrel306. Theneedle electrodes316 are mechanically linked to a finger-operatedpull lever318 on thehand grip304. By operation of thepull lever318, the distal ends of theneedle electrodes316 are moved between a retracted position (FIG.5) and an extended position (FIG.6 of the ‘523 patent). An electrical insulatingmaterial344 is coated about the needle electrodes316 (seeFIG.6 of the ‘523 patent), except for a prescribed region of the distal ends, where radio frequency energy is applied to tissue. Thegenerator38 is coupled via thecable10 to aconnector352, to convey radio frequency energy to theelectrodes316.
• In use (seeFIG.8), the physician grasps thehand grip304 and guides thebarrel306 into theanal canal320. Thepull lever318 is in the neutral position and not depressed, so theneedle electrodes316 occupy their normal retracted position. Looking through theviewing port312, the physician visualizes the pectinate (dentate) line through thebarrel306. Looking through thebarrel306, the physician positions the distal ends of theneedle electrodes316 at a desired location relative to the pectinate (dentate) line. A fiberoptic can also be located in thebarrel306 to provide local illumination. Once the distal end of thebarrel306 is located at the targeted site, the physician depresses the pull lever318 (asFIG.8 shows). Theneedle electrodes316 advance to their extended positions. The distal ends of theelectrodes316 pierce and pass through the mucosal tissue into the muscle tissue of the target sphincter muscle. InFIG.8, the distal end of theelectrodes316 are shown penetrating the involuntary,internal sphincter muscle322. The physician commands thecontroller52 to apply radio frequency energy through theneedle electrodes316. The energy can be applied simultaneously by allelectrodes316, or in any desired sequence.
• The externalfluid delivery apparatus44 is coupled viatubing12 to aconnector348 to convey a cooling liquid, e.g., through holes in thebarrel306, to contact tissue at a localized position surrounding theelectrodes316. Theexternal aspirating apparatus46 is coupled viatubing14 to aconnector350 to convey liquid from the targeted tissue site, e.g., through anaspiration port358 in thedistal end308 of the barrel306 (seeFIGS.6 and7).
• The barrel306 (seeFIG.7) also preferably carries temperature sensor364, one of which is associated with eachneedle electrode316. The sensors364 sense tissue temperature conditions in the region adjacent to eachneedle electrode316. Preferably, the distal end of eachneedle electrode316 also carries a temperature sensor372 (seeFIG.7).
• In use (seeFIG.9), a preferred pattern of multiple lesions is formed comprising several circumferential rings of lesions in axially spaced-apart levels (about 5 mm apart), each ring comprising 16 lesions in four quadrants of 4 each. The rings are formed axially along the anal canal, at or near the dentate line.
• Thefluid delivery apparatus68 conveys cooling fluid for discharge at the treatment site, to cool the mucosal surface while energy is being applied by theneedle electrodes316. The aspiratingapparatus76 draws aspirated material and the processing fluid through thetubing78 for discharge.
• Referring toFIG.9, the array ofneedle electrodes316 is positioned atLevel 1 to create four multiple lesions in the first quadrant. Upon the satisfactory creation of the lesion pattern in the first quadrant ofLevel 1, as just described, the physician actuates the button64 to release the lockingpawl58 from thedetent62. Thepull lever318 returns to the spring-biased neutral position, thereby moving theneedle electrodes316 back to their retracted positions. Still grasping thehand grip304 and visualizing through theviewing port312, the physician moves thebarrel 5 mm axially upward toLevel 2, the first quadrant. The physician again deploys theneedle electrodes316 and performs another lesion generating sequence. The physician repeats this sequence of steps until additional number of lesion patterns are formed within the axially spaced first quadrants inLevels 1, 2, 3, 4, and 5.
• Still grasping thehand grip304 and visualizing through theviewing port312, the physician returns tolevel 1, and rotates the barrel306 a selected arcuate distance at the level of the first lesion pattern94 to the second quadrant, i.e., by rotating thebarrel306 by ninety degrees.
• The physician again deploys theneedle electrodes316 and performs another lesion generating sequence atquadrant 2 ofLevel 1. The physician then moves the barrel axially upward in 5 mm increments, at a number of axially spacedlevels 2, 3, 4, and 5 generally aligned withlesion patterns96,98, and100. Lesions are formed in this way in the second quadrant ofLevels 1, 2, 3, 4, and 5.
• The physician repeats the above described sequence two additional times, returning the barrel tolevel 1 and rotating thebarrel306 at successive intervals and axially repositioning thebarrel306 to form thelesion patterns quadrants 3 and 4 in theLevels 1, 2, 3, 4, and 5. This protocol forms acomposite lesion pattern102, which provides a density of lesions in the targeted sphincter tissue region to provoke a desired contraction of the sphincter tissue.
III. System Operation
• In the illustrated embodiment (seeFIGS.10A and10B), theradio frequency generator38, thecontroller52 with I/O device54, and the fluid delivery apparatus44 (e.g., for the delivery of cooling liquid) are integrated within asingle housing400.
• The I/O device54 couples thecontroller52 to a display microprocessor474 (seeFIG.10A). Thedisplay microprocessor474 is coupled to a graphics display monitor420 in thehousing400. Thecontroller52 implements through thedisplay microprocessor474 the graphical user interface, or GUI, which is displayed on thedisplay monitor420. The graphical user interface can be realized with conventional graphics software using the MS WINDOWS® application. The GUI is implemented by showing on themonitor420 basic screen displays.
A. Set-Up
• Upon boot-up of the CPU (seeFIG.11), the operating system implements the SET-UP function for theGUI500. The GUI displays an appropriate start-up logo and title image (not shown), while thecontroller52 performs a self-test. An array of SETUP prompts502 leads the operator in a step-wise fashion through the tasks required to enable use of the generator and device. The physician can couple the source of cooling liquid to the appropriate port on the handle of the device26a/26b (seeFIG.10A, as previously described) and load the tubing leading from the source of cooling liquid (e.g., a bag containing sterile water) into the pump rotor428 (seeFIG.10B). The physician can also couple theaspiration source46 to the appropriate port on the handle of the treatment device26a/26b (as also already described). The physician can also couple thepatch electrode412 and foot pedal416 (shown inFIG.10A). In the SET-UPprompt array502, a graphic field of theGUI500 displays one or more icons and/or alpha-numeric indicia502 that prompt the operator to connect thereturn patch electrode412, connect the foot pedal orswitch416, connect the selected treatment device26a (designed by its trademark STRETTA®) or26b (designated by its trademark SECCA®), and to prime theirrigation pump44.
• Note in some embodiments, the user controls the pump speed to increase fluid flow if the temperature is rising. In alternate embodiments, the system is designed with an automatic cooling feature, thus enabling quicker application of cooling fluid to address rising tissue temperatures to faster cool the tissue surface which in turn cools the underlying tissue which helps to maintain the tissue temperature below the “tissue ablation threshold.”
• More specifically, at certain tissue temperatures, the speed of the pump is changed automatically to reduce the temperature. That is, if the tissue surface temperature, e.g., at the mucosa layer as measured by the tissue temperature sensor, reaches a certain threshold (a “first value”), the pump speed will increase to pump more cooling fluid to the tissue. In some embodiments, for certain tissue temperature values, the system can enable the user to override the automatic pump to reduce the fluid flow. In other embodiments, a user override feature is not provided. In either case, the system is preferably designed so that if a second predetermined higher temperature value (“second value”) is reached, the pump is automatically moved to its maximum pump speed, which preferably cannot be overridden by the user. When a third predetermined still higher tissue temperature value is reached (a “third cutoff value”), the electrode channel is disabled as discussed herein to shut off energy flow to that electrode. Consequently, before the third cut off value is reached, as the temperature is rising, the system provides for a quicker response to the rising temperature by automatically increasing fluid flow, rather than relying on the slower response time of the user to implement the pump speed change, thereby helping to keep temperature below the tissue ablation threshold temperature.
• Exemplary tissue values are provided solely by way of example, it being understood that other tissue values can also be utilized to achieve quick application of cooling fluid and ensure the non-ablation, and non-burning, of tissue. For example, in the upper GI tract treatment device described herein (seeFIG.3), the first value could be about 38 degrees, the second predetermined value could be about 40 degrees and the third value where the energy is shut down could be about 43 degrees. For a lower GI tract treatment device described herein (seeFIG.6), the first value could be about 45 degrees, the second predetermined value could be about 46 degrees and the third value where the energy is shut down could be about 54 degrees.
• Thecontroller52 ascertains whichdevice26a or26b has been selected for use by reading a coded identification component residing in the handle of thedevice26a or26b. Based upon this input, thecontroller52 proceeds to execute the preprogrammed control and graphical GUI command functions for theparticular device26a and26b that is coupled to the generator.
• If the identification code for the device26a, (STRETTA®) is registered, the GUI displays an appropriate start-up logo and title image for the device26a (seeFIG.12). Likewise, if the identification code for thedevice26b (SECCA®) is registered, the GUI displays an appropriate start-up logo and title image for thedevice26b (FIG.13).
• In some embodiments, the coded identification device is part of a printed circuit board (PCB) positioned in the handle of the treatment device. The PCB for each device is illustrated generally inFIGS.2A and6A, and designated byreference numerals29,329, respectively, and processes the calculated parameters. The PCB in conjunction with thermocouples provides a temperature measurement mechanism. The PCB measures the voltage generated by the thermocouples, converts it from an analog to a digital value and stores it in the internal memory. Upon request by the generator, the PCB communicates the digital data to the generator. This step is performed during the 100 millisecond break between radiofrequency pulses discussed below. By placement of the temperature measurement mechanism in the treatment device, i.e., in the disposable handpiece, rather than in thehousing400, data collection is closer to the source which translates into less noise susceptibility and improved accuracy. That is, since processing of temperature values occurs closer to the tissue and electrode tip, measurements can be more accurate. More accurate readings translate into tighter power controls and better clinical results and it better ensures the tissue is not ablated during treatment as it is maintained below a tissue ablation threshold.
• In a preferred embodiment, the PCB, which is asymmetrically positioned within the handle, is shielded to reduce interference which could otherwise disrupt communication between the disposable treatment device and the generator. Such interference (noise) could corrupt the data and unnecessarily result in system errors which can unnecessarily shut down energy flow to the electrode(s) during the procedure. In a preferred embodiment, the shield is a copper foil, although other ways to shield the PCB are also contemplated. In other words, the disruption of communication could adversely affect processing and evaluation of the data collected by the treatment device. By eliminating such disruptions, and thereby disabling fewer electrodes, improved consistency of treatment is achieved. Also, as can be appreciated, if too many electrodes are disabled in a procedure, the tissue may not be sufficiently thermally treated to achieve the desired clinical result.
• In an alternate embodiment of the treatment devices shown inFIGS.2B and6B, the identification code is positioned in the handle of thetreatment device26a,26b, generally designated by reference numerals29a,329a, respectively, but the other hardware, e.g., the printed circuit board for temperature calculation, etc. is outside the handle and represented generally byreference numeral49 inFIG.2B andreference numeral340 inFIG.6B. Thus, the temperature data collection is performed outside the disposable treatment device which reduces costs since it need not be disposed of with the disposable treatment device. Note the embodiments ofFIGS.2B and6B still have the advantage of data collection closer to the source than if in thehousing400.
B. Treatment Screens (UGUI and LGUI)
• Upon completion of the SET-UP operation, thecontroller52 proceeds to condition the generator and ancillary equipment to proceed step-wise through a sequence of operational modes. The operational modes have been preprogrammed to achieve the treatment protocol and objective of the selected device26a/26b. The conduct of these operational modes and the appearance of the graphical user interface that guides and informs the user during the course of the selected procedure can differ betweendevices26a and26b.
• For ease of description, theGUI500 displays for the upper gastro-intestinal procedure (i.e., for the device26a) a treatment screen that will in shorthand be generally called UGUI504 (FIG.14A). Likewise, the GUI displays for the lower gastro-intestinal procedure (i.e., for thedevice26b) a treatment screen that will in shorthand be generally called LGUI506 (FIG.15A).
• In both the UGUI504 (FIG.14A) and LGUI506 (FIG.15A), there is aparameter icon462 designating cooling fluid flow rate/priming. In both theUGUI504 and theLGUI506, the Flow Rate/Priming Icon462 shows the selected pump speed by the number of bars, one bar highlighting a low speed, two bars highlighting a medium speed, and three bars highlighting a high speed.
• Each UGUI504 (FIG.14A) and LGUI506 (15A) includes anElectrode Icon466. In general, eachElectrode Icon466 comprises an idealized graphical image, which spatially models the particular multiple electrode geometry of the treatment device26a/26b that has been coupled to the controller42. Just as the multiple electrode geometries of thedevices26a and26b differ, so, too, does theElectrode Icon466 of theUGUI504 differ from theElectrode Icon466 of theLGUI506.
• AsFIG.14A shows, in theUGUI504, four electrodes are shown in the graphic image of theIcon466, which are spaced apart by 90 degrees. This graphic image reflects the geometry of the four-electrode configuration of the device26a, as shown inFIG.4.
• AsFIG.15A shows, in theLGUI506, four electrodes are shown in the graphic image ofIcon466 in a circumferentially spaced relationship along a partial arcuate sector. This graphic image reflects the arrangement of electrodes on thetreatment device26b, as shown inFIG.7.
• For each electrode, therespective Icon466 incorporates graphic regions O1, O2, and O3 in the spatial display. Regions O1 and O2 display temperature conditions encountered for that electrode. Region O1 numerically displays the magnitude of sensed electrode tip temperature in UGUI504 (FIG.14A) and LGUI506 (FIG.15A). Region O2 numerically displays sensed tissue temperatures for that electrode in UGUI504 (FIG.14A) and LGUI506 (FIG.15A). Region O3 displays the derived impedance value for each electrode. BothUGUI504 andLGUI506 display instantaneous, sensed temperature readings from the tip electrode and tissue surface, as well as impedance values, which are continuously displayed in spatial relation to the electrodes in the regions O1, O2, and O3.
• The numeric displays of the regions O1/O2/O3 can be blanked out for a given electrode if the corresponding electrode/channel has been disabled, either by the physician or by a sensed out-of-bounds condition. An “acceptable” color indicator (e.g., green) can also be displayed in the background of the regions O1/O2/O3 as long as the sensed condition is within the desired preestablished ranges. However, if the sensed conditions fall outside the desired range, the color indicator changes to an “undesirable” color indicator (e.g., to grey), and numeric display is blanked out.
• In a preferred embodiment, if an electrode/channel is disabled and the energy is turned off for that electrode, the corresponding icon is grayed out, but the numeric value remains on the screen, thus providing useful information to the user. Thus, at the end of the surgical procedure, the reasons for the shut down of the particular electrode can be evaluated so the user can learn what if any user errors occurred.
• In some embodiments, temperature of the needle tips is measured when the needles are deployed at the lesion level, but prior to application of RF energy. If the measured temperature exceeds an expected value, the temperature reading alerts the user that the needle position might need to be readjusted. If the temperature value is too high, this can mean that the electrode position is too close to the previous tissue level treated, and thereby the user can readjust the electrode position by increasing the spacing, thereby reducing the chances of overtreating the tissue which can cause undesired tissue ablation or burning of tissue. Consequently, continuous treatment of tissue can be achieved with reduced overlapping of treatment.
• Also, as can be appreciated, the temperature of the electrode tip, the tissue temperature and the impedance, along with other safety parameters, such as adequate connections, are monitored during the procedure to ensure energy flow is correct. This includes proper flow through the cable, electrodes, ground pad, etc. The electrode needle is then disabled if a safety condition is suspected and indicated. Each needle can be controlled separately.
• In use of the system, impedance is intermittently checked throughout the procedure. Impedance is measured by measuring the current at the channel of the electrode tip. The impedance monitoring provides an indication of how well the treatment device is connected and communicating with the tissue, which includes the needle penetration and the path with the return pad. If there is not good contact between the electrode and tissue, impedance is high and a patient can get burned. Therefore, if a patient moves, needle penetration could be affected. However, oftentimes a minor adjustment can be made which does not require shutting down energy flow. To avoid premature shutting down of the system a multiple error check is conducted by the system which is described in more detail below. This multiple error check reduces the incidence of needle disabling which in turn reduces the incidence of undertreatment.
• Note the impedance is measured by applying a voltage, measuring the current and calculating the impedance. The RF energy is applied in 0.9 second intervals, with a 0.1 second break in between where an artificial pulse is sent for 0.1 second, in which impedance is measured. The temperature of the electrode tip and tissue temperature is also measured during this 0.1 second interval, for calculating such measurement. Preferably, the RF energy is repeatedly applied for 0.9 seconds, with 0.1 second “measurement intervals” for a time period of 60 seconds.
• There is also aLesion Level Icon510 in eachdisplay UGUI504 andLGUI506, adjacent to therespective Electrode Icon466. TheLesion Level Icon510 comprises an idealized graphical image, which spatially models the desired lesion levels and the number of lesions in each level. Just as the lesion patterns created by thedevices26a and26b differ, so, too, does theLesion Level Icon510 of theUGUI504 differ from theElectrode Icon466 of theLGUI506.
• As will be described in greater detail later, theLesion Level Icons510 change in real time, to step-wise guide the physician through the procedure and to record the progress of the procedure from start to finish. In many fundamental respects, the look and feel of theLesion Level Icons510 for theLGUI504 and theLGUI506 are similar, but they do differ in implantation details, due to the difference of the protocols of lesion formation.
• Exemplary changes in theLesion Level Icons510 for theUGUI504 and theLGUI506 will now be described.
1. The UGUI
• In the UGUI504 (seFIG.14A), six numberedLesion Levels 1, 2, 3, 4, 5, and 6 are displayed, to correspond with the lesion levels already described and shown inFIG.5. TheUGUI504 also displays asquiggle line514, which marks where the physician has visualized a selected anatomic home base reference for the formation of lesions within the esophagus for treatment. Guided by theUGUI504, lesions are placed relative to this anatomic home base.
• In preparation for the treatment, the physician visualizes in the esophagus the Z-line or other desired anatomic landmark. Markers are arranged at 5 mm intervals along the catheter tube. Upon visualizing the Z-line, the physician notes the external marker on the catheter tube that corresponds to this position. With reference to the markers, the physician can then axially advance or retract the catheter tube in 5 mm increments, which correspond to the desired spacing between the lesion levels. This orientation of lesion levels is also shown inFIG.5.
• TheUGUI504 graphically orients the location ofLesion Levels 4, 5, and 6 relative to this anatomical base, displaying Lesion Levels either below (inferior to) the squiggle line514 (Lesion Levels 4, 5, and 6) or at or above the squiggle line514 (Lesion Levels 1, 2, and 3) .
• As will be described, theUGUI504 graphically changes the display of the Lesion Levels, depending upon the status of lesion formation within the respective levels.
• FIG.14A shows a representative first graphical form of a given lesion level. The graphical form comprises, e.g., a cylinder that faces edgewise on theUGUI504, as is shown forLesion Levels 1 to 6 inFIG.14A. This graphical form indicates at a glance that no lesions are present in the respective lesion levels.
• As is shown inFIG.14A, next to the graphical form of the edgewise cylinder ofLesion Level 1 is aGuide Marker512. TheGuide Marker512 indicates that formation of lesions inLesion Level 1 is the first to be indicated. A numeric value (15 mm) is displayed in association with the edgewise cylinder ofLesion Level 1, which indicates thatLesion Level 1 is 15 mm from the anatomic landmark. The orientation ofLesion Level 1 above (superior to) thesquiggle line514 guides the physical to advance the catheter tube upward from the anatomic marker by 15 mm, to place it atLesion Level 1. ABalloon Icon516 prompts the physician to expand the basket of the device26a atLesion Level 1.
• Upon sensing electrode impedance, indicating contact with tissue at Lesion Level 1 (or in response to another input indicating deployment of the device26a at the desired lesion level), the controller commands theUGUI504 to change the graphical form ofLesion Level 1 to a second graphical form, which is shown inFIG.14B. The second graphical form (shown inFIG.14B) is different than the first graphical form (shown inFIG.14A). The graphical form comprises, e.g., a segmented circle, with a numeric indicator next to it. This is shown forLesion Level 1 inFIG.14B. In visual effect, the second graphical form shows the previously cylinder form rotated for viewing along its axis. The number of segments shown (inFIG.14B, there are eight segments) corresponds with the number of lesions that are to be formed atLesion Level 1.
• InFIG.14B, all segments of the circle are unmarked. This graphical form indicates at a glance that (i) formation of lesions at this lesion level is now indicated (due to the axial circle view of the lesion level icon), (ii) eight circumferentially spaced lesions are to be formed (due to the number of segments); (iii) no lesions have as yet been formed (by the lack of other markings in the segments).
• The location of theMarker512 also changes to align withLesion Level 2, with a numeric indicator of 5 mm. This informs the physician that, afterLesion Level 1, the next lesion level to be treated isLesion Level 2, which is 5 mm below (inferior to)Lesion Level 1.
• With the device26a positioned atLesion Level 1, the physician actuates the electrodes for a first pre-set period. Theballoon icon516 disappears as treatment progresses on a given level. ATimer Icon518 shows the application of radio frequency energy for the pre-set period. At the end of this pre-set period (seeFIG.14C), treatment indicia (e.g., dots) appear in four segments of the graphical segmented circle, indicating the formation of the first four lesions, as well as their spatial orientation.
• The open segments remaining in the segmented circle prompt the physician to rotate the basket by 45-degrees, and actuate the electrodes for second time. After the pre-set period (tracked by the Timer Icon518) (seeFIG.14D), more treatment indicia (the dots) appear in the remaining segments of the circle. This indicates that all the lesions prescribed forLesion Level 1 have been formed, and to deflate the basket and move to the next treatment level. TheMarker512 that is displayed directs the physician toLesion Level 2, which is 5 mm belowLesion Level 1. TheBalloon Icon516 can reappear to prompt the physician to deflate the balloon.
• The physician is thereby prompted to deflate the basket, move toLesion Level 2, and expand the basket. AsFIG.14E shows, upon sensing electrode impedance, indicating contact with tissue atLesion Level 2, theUGUI504 changes the graphical form ofLesion Level 1 back to an edgewise cylinder. The edgewise cylinder forLesion Level 1 includes an indicator, e.g., checkmark, to indicate thatLesion Level 1 has been treated (as shown inFIG.14E). The insertion of the treatment completed indicator is yet another graphical form theUGUI504 displays to communicate status information to the physician.
• Also referring toFIG.14E, upon sensing electrode impedance, indicating contact with tissue atLesion Level 2, theUGUI504 changes the graphical form ofLesion Level 2 to the second graphical form, comprising, e.g., the segmented circle, as already described. This is shown forLesion Level 2 inFIG.14E. The location of theMarker512 also changes to align withLesion Level 3, with a numeric indicator of 5 mm. This informs the physician that afterLesion 2, the next lesion level will beLesion Level 3, which is 5 mm below (inferior to)Lesion Level 2.
• As shown inFIGS.14F and14G, with the device26a positioned atLesion Level 2, the physician actuates the electrodes for a first pre-set period, then rotates the device26a 45-degrees, and actuates the electrodes for the second pre-set period. TheTimer Icon518 reflects the application of radio frequency energy for the pre-set periods, and the treatment indicia (e.g., dots) are added to the segments of the graphical segmented circle, indicating the formation of the first four lesions (FIG.14F) and the next four lesions (FIG.14G), as well as their spatial orientation.
• Upon formation of the eight lesions inLesion Level 2, theballoon icon518 again appears. This indicates that all the lesions prescribed forLesion Level 2 have been formed, and to deflate the basket and move to the next treatment level. TheMarker512 that is displayed directs the physician toLesion Level 3, which is 5 mm belowLesion Level 2.
• The physician is thereby prompted to deflate the basket, move toLesion Level 3, and expand the basket. Upon sensing electrode impedance, indicating contact with tissue at Lesion Level 3 (seeFIG.14H), theUGUI504 changes the graphical form ofLesion Level 2 back to an edgewise cylinder (asFIG.14H shows). The edgewise cylinder forLesion Level 2 now includes an indicator, e.g., the checkmark, to indicate thatLesion Level 2 has been treated (asFIG.14H also shows).
• AsFIG.14I also shows, upon sensing electrode impedance, indicating contact with tissue atLesion Level 3, theUGUI504 changes the graphical form ofLesion Level 3 to the second graphical form, comprising, e.g., the segmented circle, as already described. This is shown forLesion Level 3 inFIG.14H. The location of theMarker512 also changes to align withLesion Level 4, with a numeric indicator of 5 mm. This informs the physician that afterLesion 3, the next lesion level will beLesion Level 3, which is 5 mm below (inferior to)Lesion Level 3.
• The physician proceeds to form eight lesions in Lesion Level 3 (FIGS.14I and14J), then moving on to Lesion Level 4 (not shown, but following the same progression as already described). All the while, theUGUI504 visually records and confirms progress. As shown inFIG.14K, the graphical Lesion Level cylinders forLesion Levels 3 and 4 return edgewise when the desired number of lesions has been formed on the respective level and treatment at the level has been completed. At that time, a check mark appears on the edgewise cylinder, indicating that treatment at that level has been completed forLesion Levels 1, 2, 3, and 4 (as shown inFIG.14K).
• InFIGS.14K to14N, onLesion Levels 5 and 6, the segments in the segmented circle number twelve, indicating that twelve lesions are to be formed on these levels. In theLevels 5 and 6, there are twelve lesions circumferentially spaced 30-degrees apart (i.e., a first application of energy, followed by a 30-degree rotation of thebasket56, followed by a second application of energy, followed by a 30-degree rotation of thebasket56, followed by a third application of energy). InLevel 5, the balloon structure is only partially expanded, whereas inLevel 6, theballoon structure72 is more fully expanded, to provide lesion patterns that increase in circumference according to the funnel-shaped space available in the funnel of the cardia.
• TheUGUI504 reflects completion of the treatment (seeFIG.14O).
• In preferred embodiments, a series of icons related to balloon inflation are displayed on the graphical user interface. More specifically, as soon as the system is ready to begin treatment, a pressure relief valve icon as depicted inFIG.14P appears on the treatment screen (see alsoFIG.14Q). Thisicon550 serves as a reminder to the user to utilize the relief valve, as described above, to prevent overinflation of the balloon at Lesion Levels 1-4. As soon as the treatment cycle begins, therelief valve icon550 disappears from the screen. After treatment at Lesion Levels 1-4, before treatment atLevel 5 begins,balloon icon552, which has a 25 ml label, appears to indicate inflation of the balloon to 25 ml.Icon552 disappears when treatment atLevel 5 begins. Before treatment atLevel 6,balloon icon554 with a 22 ml label to remind the user to deflate the balloon to 22 ml appears.Balloon icon554 disappears from the screen when treatment atLevel 6 begins.
• Thus, theUGUI504, by purposeful manipulation of different stylized graphical images, visually prompts the physician step wise to perform a process of forming a pattern of lesions comprising a plurality of axially spaced lesion levels, each lesion level comprising a plurality of circumferential spaced lesions. TheUGUI504 registers the formation of lesions as they are generated in real time, both within and between each circumferentially spaced level. TheUGUI504 therefore displays for the physician a visual record of the progress of the process from start to finish. TheUGUI504 assures that individual lesions desired within a given level are not skipped, or that a given level of lesions is not skipped.
• In the UGUI508, eachLesion Level 1 to 6 is initially depicted by a first stylized graphical image comprising an edgewise cylinder with a number identification of its level. When the formation of lesions at a given level is indicated, theUGUI504 changes the first stylized graphical image into a second stylized graphical image, different than the first image, comprising an axial view of the cylinder, presented as a segmented circle, with the numbers of segments corresponding to the number of lesions to be formed. There also appears juxtaposed with the next lesion level to be treated (still displayed as an edgewise cylinder), a marker along with a number indicating its distance from the present legion level. As the physician manipulates the device26a to form lesions on the indicated levels, the second graphical image further changes to a third graphical image, different than the first or second images, by adding indicia within the segmented circle to reflect the formation of lesions, to guide the physician to successively rotate and operate the device26a at the lesion level. Upon forming the desired lesion pattern on a given level, theUGUI504 again changes the third graphical image to a fourth graphical image, different than the first, second, and third graphical images, comprising an edgewise cylinder with a number identification of its level, and further an indicator (e.g. a check mark) that indicates all desired lesions have been formed at the respective level. AMarker512 is successively updated to direct the physician to the next Lesion Level. In this way, theUGUI504 prompts the formation of eight lesions circumferentially spaced 45-degrees apart in theLevels 1, 2, 3, and 4, and the formation of twelve lesions circumferentially spaced 30-degrees apart atLesion Levels 5 and 6. Thus, a total of 56 lesions can be formed in this procedure.
2. The LGUI
• The LGUI506 (FIG.15A) generates a graphical user display that guides the physician in manipulating thedevice26b to form a prescribed lesion pattern in the anal canal, as shown inFIG.9. The lesion pattern comprises a plurality of axially spaced lesion levels (in the illustrated embodiment, numbered 1 to 5), each lesion level comprising a plurality of circumferential spaced lesions (In the illustrated embodiment, there are sixteen lesions, arranged in sets of four).
• The display of the LGUI506 (seeFIG.15A) showsLesion Levels 1, 2, 3, 4, and 5, corresponding with the multiple lesion levels to be formed in the anal canal.Lesion Levels 1 to 5 are displayed as segmented discs, numbered 1 to 5, which are tilted slightly on their axes, and arranged one above the other. Each disc is divided into four quadrants.
• TheLGUI506 also shows (seeFIG.15A) adentate squiggle line514. In preparation for the treatment, the physician visualizes in the anal canal dentate line or other desired anatomic landmark. Markers are arranged at 5 mm intervals along the barrel of thedevice26b. Upon visualizing the dentate line, the physician notes the external marker on the barrel that corresponds to this position. With reference to the markers, the physician can then axially advance or retract the barrel in 5 mm increments, which correspond to the spacing between the lesion levels.
• Next to the graphical form of the disc ofLesion Level 1 is a Guide Marker512 (seeFIG.15A). TheGuide Marker512 indicates that formation of lesions inLesion Level 1 is indicated. A numeric value (5 mm) is displayed in association with the edgewise cylinder ofLesion Level 1, which indicates thatLesion Level 1 is 5 mm from the anatomic landmark.
• InFIG.15A, all quadrants of the lesion level discs are unmarked. This graphical form indicates at a glance that (i) formation of lesions atLesion Level 1 is now indicated (due to the position of the Marker512) and (ii) no lesions have as yet been formed (by the lack of markings in the quadrants).
• Thedevice26b includes an array of four needle electrodes arranged in an arc, which can be advanced and retracted (seeFIG.6). The array of needle electrodes is positioned atLevel 1, in alignment withquadrant 1, and advanced. The physician actuates the electrodes for a first pre-set period. ATimer Icon518 shows the application of radio frequency energy for the pre-set period. At the end of this pre-set period, treatment indicia (e.g., four dots) appear in the first quadrant of the graphical segmented discs (seeFIG.15B), indicating the formation of the first four lesions, as well as their spatial orientation in the first quadrant.
• The location of theMarker512 also changes to align withLesion Level 2, with a numeric indicator of 5 mm. This informs the physician that afterLesion Level 1, the next lesion level will beLesion Level 2, which is 5 mm above (superior to)Lesion Level 1.
• Upon the satisfactory creation of the lesion pattern in the first quadrant ofLevel 1, as just described, and as prompted by the Marker512 (now aligned with Lesion Level 2), the physician actuates the button to move the needle electrodes back to their retracted positions. Still grasping the hand grip and visualizing through the viewing port, the physician moves thebarrel 5 mm axially upward toLevel 2, remaining rotationally aligned in the first quadrant. The physician again deploys the needle electrodes and performs another lesion generating sequence. The location of theMarker512 also changes to align withLesion Level 3, with a numeric indicator of 5 mm. This informs the physician that afterLesion Level 2, the next lesion level will beLesion Level 3, which is 5 mm above (superior to)Lesion Level 2. Treatment indicia (e.g., four dots) appear in the first quadrant of the graphical segmented disc of Lesion Level 2 (seeFIG.15C), indicating the formation of the four lesions, as well as their spatial orientation in the first quadrant.
• The physician repeats this sequence of steps until additional number of lesion patterns are formed within the axially spaced first quadrants inLevels 2, 3, 4, and 5 (seeFIGS.15D,15E, and15F). The location of theMarker512 also changes to align with successive Lesion Levels, to guide the physician through the lesion levels. Treatment indicia (e.g., four dots) appear in the first quadrant of the graphical segmented discs ofLesion Levels 2, 3, 4, and 5 (seeFIG.15F), indicating the formation of the four lesions, as well as their spatial orientation in the first quadrant.
• Upon formation of the four lesions inquadrant 1 ofLesion Level 5, theMarker512 returns to Lesion Level 1 (seeFIG.15F), prompting the physician to return toLesion Level 1, and again rotate the barrel a selected arcuate distance atLesion Level 1 into alignment with the second quadrant, i.e., by rotating the barrel by ninety degrees.
• Guided by theLGUI506, the physician again deploys the needle electrodes and performs another lesion generating sequence atquadrant 2 ofLevel 1. Guided by the LGUI506 (as shown inFIG.15G), and following theMarker512, the physician then moves the barrel axially upward in 5 mm increments, sequentially toquadrant 2 ofLesion Level 2, thenquadrant 2 ofLesion Level 3, thenquadrant 2 ofLesion Level 4, andquadrant 2 ofLesion Level 5. At each Lesion Level, the physician deploys the needle electrodes and performs another lesion generating sequence atquadrant 2 of the respective level. After lesion formation at each Lesion Level, treatment indicia (e.g., four dots) appear in the second quadrant of the graphical segmented discs ofLesion Levels 2, 3, 4, and 5 (seeFIG.15G), indicating the formation of the four lesions, as well as their spatial orientation in the second quadrant.
• Upon formation of the four lesions inquadrant 2 ofLesion Level 5, theMarker512 returns toLesion Level 1. The physician returns toLesion Level 1, and again rotates the barrel a selected arcuate distance atLesion Level 1 into alignment with the third quadrant, i.e., by rotating the barrel by ninety degrees.
• Guided by the LGUI506 (seeFIG.15H), the physician again deploys theneedle electrodes48 and performs another lesion generating sequence atquadrant 3 ofLevel 1. Treatment indicia (e.g., four dots) appear in thequadrant 3 of the graphical segmented disc ofLesion Levels 1, indicating the formation of the four lesions, as well as their spatial orientation in the third quadrant.
• As shown inFIG.15H, guided by theLGUI506, and following theMarker512 as it advances with lesion formation at each level, the physician then moves the barrel axially upward in 5 mm increments, sequentially toquadrant 3 ofLesion Level 2, thenquadrant 3 ofLesion Level 3, thenquadrant 3 ofLesion Level 4, andquadrant 3 ofLesion Level 5. At each Lesion Level, the physician deploys the needle electrodes and performs another lesion generating sequence atquadrant 3 of the respective level. Treatment indicia (e.g., four dots) appear in the third quadrant of the graphical segmented discs ofLesion Levels 2, 3, 4, and 5 (seeFIG.15H), indicating the formation of the four lesions, as well as their spatial orientation in the third quadrant.
• The physician repeats the above described sequence one additional time, returning the barrel toLesion Level 1 and rotating the barrel ninety degrees into alignment withquadrant 4 of Lesion Level 1 (seeFIG.15I). The physician forms thelesion patterns quadrant 4 in theLevels 1, 2, 3, 4, and 5. Treatment indicia (e.g., four dots) appear in the fourth quadrant of the graphical segmented discs ofLesion Levels 1, 2, 3, 4, and 5 (seeFIG.15B), indicating the formation of the four lesions, as well as their spatial orientation in the second quadrant. In addition, with the formation of lesions in the fourth quadrant at each Lesion Level, the graphical disc representing the Lesion Level, each quadrant marked by four dots (indicating completion of lesion creation) is changed to additionally include an indicator, e.g., checkmark, to indicate that the respective Lesion Level has been treated (seeFIG.15I).
• As can be appreciated, there are twenty potential treatments with the device. That is, with the device deploying four needles, and ultimately four treatments at each of the Levels 1-5, potentially 80 lesions can be formed. Note that each treatment is preferably timed for sixty seconds, although other cycles/intervals are also contemplated. Note also that each needle electrode can be controlled independently.
• As described, theLGUI506 visually prompts a user in a step-wise fashion to perform a process of forming a pattern of lesions in the anal canal comprising a plurality of axially spaced lesion levels, each lesion level comprising a plurality of circumferential spaced lesions. TheLGUI506 registers the formation of lesions as they are generated in real time, both within and between each circumferentially spaced level. TheLGUI506 displays for the user a visual record of the progress of the process from start to finish and guides the user so that individual lesions desired within a given level are all formed, and that a given level of lesions is not skipped.
• EachLesion Level 1 to 5 of theLGUI506 is depicted by a first stylized graphical image comprising an edge-tilted disc with a number identification of its level. The discs are segmented corresponding to the regions in which lesions to be formed. There also appears juxtaposed with the next lesion level to be treated, a marker along with a number indicating its distance from the present legion level. As the physician manipulates thedevice26b to form lesions on the indicated levels, the first graphical image further changes to a second graphical image, different than the first image, by adding indicia within the segmented circle to reflect the formation of lesions, to guide the physician as the device is successively operated at the lesion level. Upon forming the desired lesion pattern, theUGUI506 again changes the second graphical image to a third graphical image, different than the first and second graphical images, comprising an indicator (e.g. a check mark) indicating that all desired lesions have been formed at the level. TheMarker512 is updated to direct the physician to the next Lesion Level. In this way, theUGUI506 prompts the formation of four lesions sets of four lesions each (totaling twelve lesions) circumferentially spaced apart in theLevels 1, 2, 3, 4, and 5.
• During the procedure utilizing either of theradiofrequency treatment devices26a or26b, certain error messages are graphically indicated on the GUI. Certain of these error messages relate to user errors which could be in the user’s control, and therefore could potentially be correctable by the user. For example, if there is an error in the treatment device connection, the generator returns to the set up screen and the icon representing the treatment device displayed by the GUI begins flashing. Another example is if the error relates to the return pad, e.g., improper placement or contact of the pad, the generator likewise returns to the set up screen and the return pad icon displayed by the GUI begins flashing. Another example is if the needles are not treated properly. With these errors indicated, the user can attempt to make the proper adjustments, e.g., check the connection of the treatment device, adjust the position of the return pad, etc. By easily identifying these correctible errors, the system will shut down fewer times thereby enabling the creation of more lesions. Stated another way, the instrument continuously measures temperature which is transmitted back to the generator. The generator expects the temperature to be in a certain range. If the temperature does not appear right, e.g., is outside an expected range, if the RF channel was immediately shut down, then it could result in premature/unnecessary termination of RF energy which could undertreat tissue. Therefore, the present invention provides steps to ensure a shut down result is truly necessary, thus advantageously limiting undertreatment of the tissue. Similarly, if calculated impedance from current measurement does not appear correct, i.e., is outside a desired range, e.g. 50-500 ohms for the instrument ofFIG.6 and 50-100 ohms for the instrument ofFIG.2, the system of the present invention ensures that a channel shut down is warranted before shut down, again avoiding premature/unnecessary termination of RF energy which can result in undertreatment of tissue.
• The system, due to its faster processing speed which enables faster processing of data and faster adjustment of parameters, enables rechecking of detected errors to reduce the instances of prematurely shutting down energy flow to an electrode. As discussed above, premature termination of energy flow can result in insufficient application of thermal energy which in turn can result in undertreatment of tissue. In other words, the system advantageously is designed to reduce the number of events that would lead to energy cutoff to an electrode. More specifically, during the treatment cycles, oftentimes an error is detected which can be readily addressed by the user, such as by a small adjustment of the treatment device position if the error is caused for example by patient movement which affects the impedance reading, or even self-adjusts. If the system was designed to immediately shut down upon such error detection, then the electrode would be disabled and the lesion might not be created in that tissue region. Therefore, to reduce these occurrences, the system has been designed to recheck certain errors.
• More specifically, for certain detected errors, the system does not permanently interrupt energy flow on the first error reading, but suspends energy flow until a second check of the system is performed. If on the second check the error is no longer detected, energy flow is resumed. However, if on the second check, e.g., re-measurement/calculation, an error still exists, the system runs yet a third check. If the error no longer exists, the energy flow resumes; if the error still exists, energy flow is cut off to that electrode at that treatment position. Consequently, only after the system runs a triple check is a final determination made to either transition back to energy flow or record the error and disable the electrode channel, i.e., shut down RF energy flow to that electrode. Thus, the error can be checked multiple times to ensure it actually requires interruption of energy flow, thus avoiding premature disabling of an electrode to thereby enhance tissue treatment by not skipping tissue levels, or regions (quadrants) within each tissue level which could otherwise have been treated. As a result, a more comprehensive and uniform tissue treatment is achieved.
• This triple error checking feature exemplifies the speed of the processor which enables quicker processing of temperature calculations and quicker response to address rising temperatures so the tissue is not treated above the tissue ablation threshold. As noted above, this tissue ablation threshold can be exceeded if the energy is applied for too long a duration and/or too high a setting such that the tissue temperature rises or applied for too long a duration once the tissue temperature has reached the tissue ablation threshold before the flow of energy is terminated.
• Also contributing to preventing overtreatment is to ensure the spacing between the electrodes in manufacture is precise so during application of energy, the amount of overlapping in a circumferential orientation is reduced. Such accurate and consistent spacing can also prevent undertreatment such as if the two of the circumferential array of electrodes are undesirably angled or curved to much toward each other, that would mean they are angled further away from the electrode on the opposite side, possibly creating a gap in the treatment in a circumferential orientation. The axial distance of the electrodes can also affect treatment. Therefore, maintaining the proper axial distance of the electrodes, preferably with the tip terminating at the same distal distance, and maintaining the proper radial distance of the tips, preferably evenly spaced along a circumference, will aid in maintaining the treatment between the lower threshold and maximum threshold, i.e., between undertreatment and overtreatment threshold.
• The system, as noted above, also avoids ablating tissue due to careful and more accurate calibration of the tissue temperature measurement mechanism. This is basically achieved by precisely calibrating the PCB so it can read the voltage generated by the thermocouples more accurately, reducing the likelihood of heating tissue beyond the tissue ablation threshold. Thus, the PCB enables more accurate temperature measurements which in turn allows the system to disable or make the appropriate adjustment, e.g., increasing cooling fluid application, when the temperature limits are reached.
• While the above description contains many specifics, those specifics should not be construed as limitations on the scope of the disclosure, but merely as exemplifications of preferred embodiments thereof. Those skilled in the art will envision many other possible variations that are within the scope and spirit of the disclosure as defined by the claims appended hereto.

Claims (2)

1. A system for controlling operation of a radiofrequency treatment device to apply radiofrequency energy to tissue to heat tissue to create tissue lesions without ablating the tissue, the system comprising:

a first treatment device having at least one electrode for applying radiofrequency energy to tissue,

a controller including a connector to which the first treatment device is coupled for use, and

a generator for applying radiofrequency energy to the at least one electrode;

the controller further including an operation system to execute on a display screen a first graphical interface guiding use of the first treatment device, the controller visually prompting a user in a step-wise fashion to perform a process using the connected treatment device of forming a pattern of lesions in a body region in a plurality of axially spaced lesion levels, each lesion level including a plurality of circumferential spaced lesions, the controller controlling application of energy so that the tissue is thermally treated to create lesions but preventing thermal treatment beyond a threshold which would ablate the tissue.

2-25. (canceled)

Images