A method and apparatus for altering a function of neural tissue in a patient. An electromagnetic signal is applied to the neural tissue through an electrode. The electromagnetic signal has a frequency component above the physiological stimulation frequency range and an intensity sufficient to produce an alteration of the neural tissue, the alteration causing the patient to experience a reduction in pain, and a waveform that prevents lethal temperature elevation of the neural tissue during application of the electromagnetic signal to the neural tissue.
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9. A system for altering a function of at least a portion of neural function of tissue in a patient comprising:
a) a generator that generates an electromagnetic signal having at least one high frequency component above a physiologic stimulation frequency range, said ta least one high frequency component have a modulated waveform that produces alteration of the function of said at least a portion of said neural tissue when applied to said tissue through an electromagnetic signal applicator, wherein said modulated waveform has a peak voltage, said peak voltage being sufficient to produce said alteration.
7. A method for altering the function of neural tissue in a patient comprising the steps of:
a) generating an electrical signal having at least one frequency component above a physiologic stimulation frequency range, said at least one frequency component producing an alteration of at least a portion of said neural tissue, and said electrical signal having a waveform that produces an average power deposition in the neural tissue corresponding to non-lethal average temperature elevation of said at least a portion of said neural tissue when said electrical signal is applied to said neural tissue, wherein said electrical signal has a peak voltage, said peak voltage being sufficient to produce said alteration; and
b) applying said electrical signal to said neural tissue. #10#
0. 15. A method for altering the function of neural tissue in a patient comprising the steps of:
a) generating an electrical signal having at least one frequency component above a physiologic stimulation frequency range, said electrical signal output including interrupted radiofrequency waveforms having predetermined time periods of on #10# -time bursts of radiofrequency output of a first predetermined duration, each on-time burst being followed by an off-time output period of a second predetermined duration that produces an average power deposition in the neural tissue corresponding to non-lethal average temperature elevation of said at least a portion of said neural tissue when said electrical signal is applied to said neural tissue, wherein said interrupted radiofrequency waveforms each have a peak voltage, said peak voltage being sufficient to produce said alteration; and
b) applying said electrical signal to said neural tissue.
1. A system for altering a function of neural tissue in a patient comprising:
a) signal applicator adapted to apply an electrical signal output to said neural tissue;
b) a signal generator that generates a electrical signal output having at least one frequency component above a physiologic stimulation frequency range, said at least one frequency component producing an alteration of a function of at least a portion of said neural tissue, and said electrical signal output having a waveform that produces an average power deposition in the neural tissue corresponding to non-lethal average temperature elevation of said at least a portion of said neural tissue when said electrical signal output is applied to said neural tissue through said signal applicator, wherein said waveform has a peak voltage, said peak voltage being sufficient to produce said alteration; and #10#
c) a signal coupler that couples said signal generator and said signal applicator.
4. A system for altering a function of neural tissue in a patient comprising:
a) an electrode adapted to apply an amplitude modulated electrical signal to the neural tissue of the patient;
b) a signal generator that generates an amplitude modulated electrical signal having at least one frequency component above a physiological stimulation frequency range, said amplitude modulated electrical signal producing an alteration of a function of the neural tissue while producing the average power deposition in the neural tissue corresponding to non-lethal temperature elevation of said neural tissue when the amplitude modulated electrical signal is applied to the neural tissue through said electrode, wherein said amplitude modulated electrical signal has a peak voltage, said peak voltage being sufficient to produce said alteration; and #10#
c) an electrical coupling between said signal generator and said electrode to apply said multiple modulated electrical signal to said electrode.
0. 20. A system for altering a function of neural tissue in a patient comprising:
a signal applicator adapted to apply an electrical signal output to the neural tissue;
#10# a signal generator that generates an electrical signal output having at least one frequency component above a physiologic stimulation frequency range, said at least one frequency component producing an alteration of a function of at least a portion of the neural tissue, and said electrical signal output including interrupted radiofrequency waveforms having predetermined time periods of on-time bursts of radiofrequency output of a first predetermined duration, each on-time burst being followed by an off-time output period of a second predetermined duration that produces an average power deposition in the neural tissue corresponding to non-lethal average temperature elevation of said at least a portion of said neural tissue when said electrical signal output is applied to said neural tissue through said signal applicator, wherein said on-time burst has a peak voltage, said peak voltage being in a range that includes 10 volts to 30 volts or more; and a signal coupler that couples said signal generator and said signal applicator.
0. 10. A system for altering a function of neural tissue in a patient comprising:
signal applicator adapted to apply an electrical signal output to said neural tissue;
#10# a signal generator that generates an electrical signal output having at least one frequency component above a physiologic stimulation frequency range, said at least one frequency component producing an alteration of a function of at least a portion of said neural tissue, and said electrical signal output including interrupted radiofrequency waveforms having predetermined time periods of on-time bursts of radiofrequency output of a first predetermined duration, each on-time burst being followed by an off-time output period of a second predetermined duration that produces an average power deposition in the neural tissue corresponding to non-lethal average temperature elevation of said at least a portion of said neural tissue when said electrical signal output is applied to said neural tissue through said signal applicator, wherein said interrupted radiofrequency waveforms each have a peak voltage, said peak voltage being sufficient to produce said alteration; and a signal coupler that couples said signal generator and said signal applicator.
2. The system of
a temperature sensor that senses temperature of said at least a portion of the neural tissue and produces an output signal representative of said temperature; and
a frequency component intensity control to adjust the intensity of the frequency component to maintain the temperature of the neural tissue below a lethal thermal level when said electrical signal is applied to said neural tissue.
5. The system of
a modulation amplitude control that adjusts the amplitude of said amplitude modulated electrical signal.
6. The system of
8. The method of
a) sensing the temperature of said at least a portion of the neural tissue;
b) generating a temperature signal representative of the sensed temperature of said at least a portion of the neural tissue; and,
c) adjusting the intensity of the at least one frequency component in response to said temperature signal in order to maintain the average temperature of said at least a portion of the neural tissue below lethal temperature levels when the electrical signal is applied to said neural tissue. #10#
0. 11. The system of
0. 12. The system of
0. 13. The system of
0. 14. The system of
a temperature sensor that senses temperature of said at least a portion of the neural tissue and produces an output signal representative of said temperature; and
#10# a frequency component intensity control to adjust the intensity of the frequency component to maintain the temperature of the neural tissue below a lethal thermal level when said electrical signal is applied to said neural tissue.0. 16. The method of
0. 17. The method of
0. 18. The method of
0. 19. The method of
a) sensing the temperature of said at least a portion of the neural tissue; #10#
b) generating a temperature signal representative of the sensed temperature of said at least a portion of the neural tissue; and,
c) adjusting the intensity of the at least one frequency component in response to said temperature signal in order to maintain the average temperature of said at least a portion of the neural tissue below lethal temperature levels when the electrical signal is applied to said neural tissue.
0. 21. The system of
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This invention relates generally to technological advances in the medical field and systems and procedures for prolonging and improving human life. More particularly, this invention relates to a method and system for altering or modifying neural tissue in a human body by using a modulated radiofrequency generator coupled to a signal applicator system that is strategically located in tissue near a patient's neural system to relieve pain without heating it to lethal levels.
In the past, radiofrequency (RF) generators and electrodes have been applied near or in neural tissue, for relieving pain or modifying its function. By way of one example, a lesion generator identified by Model No. RFG-3C RF, available from a company named Radionics, Inc., located in Burlington, Mass., has electrodes, which may be placed near a desired neural tissue area. The desired neural tissue area is heated by radiofrequency (RF) resistive power dissipation of the generator power deposited in the tissue. In some cases, thermal monitoring by a thermo sensor in the electrode is used to control the process. It is common to form heat lesions with tissue temperatures ranging from 60 to 95 degrees Celsius (° C.). Tissue generally dies when heated to about 45° C. to 50° C., which causes the patient to suffer severe, if not, unbearable pain. The pain levels are so intense, that local or general anesthetic is often required during such a procedure. Use of local or general anesthetic exposes a patient to undesired risks, and the destructive nature of and unpleasant side effects of the radiofrequency (RF) heat lesions are limitations of this technique, which is well known. Heat lesion generators typically use continuous wave radiofrequency (RF) generators with radiofrequency ranges from 100 Kilo Hertz to several Mega Hertz. Heat lesion generators are available from several companies such as Radionics, Fisher, OWL, Elekta, Medtronic, Osypka, EPT, and so on. The theoretical aspects and use of RF lesion generators and electrodes for relieving pain and functional disorders is discussed in various papers, two of which are: (1) Cosman, et al., “Theoretical Aspects of Radiofrequency Legions and the Dorsal Root Entry Zone,” Neurosurgery 15:945-950, 1984; and (2) Cosman E R and Cosman B J, “Methods of Making Nervous System Lesions,” in Wilkins R H, Rengachary SS (eds): Neurosurgery, New York, McGraw-Hill, vol. 111, 2490-2498, 1984.
Neural stimulation has also recently become a common method for pain therapy. For neural stimulation, stimulus generators are generally used, which typically have output levels between 0 to 10 volts (or zero to several milliamperes of current criteria are used). A variety of waveforms and pulse trains in the “physiologic” frequency ranges of 0 to about 300 Hertz are also typically used. This output is delivered to electrodes placed near to in neural tissue on a temporary basis (acute electrode placement) of permanent basis (chronic electrode implants). Such simulation can relieve pain, modify neural function, and treat movement disorders. Typically, in most cases the stimulation must be sustained to have long-term effects. That is, usually when the stimulus is turned off, the pain returns or the therapeutic neural modification ceases after a short time (hours or days).
Thus, it is standard practice to use permanent implant electrodes and stimulators, which may be operated on battery power or induction driven. An example of such a commercially available system is one manufactured by Medtronic, Inc., located in Minneapolis, Minn. With permanent implant electrodes and stimulators, the stimulus is usually sustained or repeated on an essentially continuous basis for years, to suppress pain or to treat movement disorders, for example, Parkinsonism, bladder control, spasticity, etc. Stimulators deliver regular pulse trains or repetitive bursts of pulses in a range between 0 to 200 Hertz, which corresponds to a human body's physiological range of neural frequency pulse rates. This method stimulates or inhibits neural function. It does not seek to heat the neural tissue for destructive purposes as in high frequency technique.
Chronologically or permanently implanted stimulators of the type discussed above, require frequent battery changes or long-term maintenance and patient follow-up, which is expensive and inconvenient, often requiring repeated surgery.
Electrosurgical generators have commonly been used in the past for cutting and coagulating tissue in surgery. They typically comprise a high frequency, high power generator, which is connected to an electrode that delivers its high power output to explode tissue for purposes of cutting, cooking, searing, or otherwise coagulating tissue to stop bleeding. Examples of such systems are generators available from a company named Codman, Inc., located in Randolph Mass., or from a company named Valley Labs, Inc., located in Boulder, Colo., or from a company names EMC Industries, located in Montrouge, France. Such generators have high frequency output waveforms, which are either continuous waves or interrupted or modulated waves. Such generators have high power levels and duty cycles, which when applied to the electrode, shatter and macroscopically separate tissue (in a cutting mode) or heat the tissue to very high temperatures, often above cell boiling (100° C.) and charring levels (in a coagulation or cauterizing mode). It should be recognized that the purpose of electrosurgery generators is surgical, not therapeutic. Thus, their output controls, power ranges, duty cycles, waveforms, and monitoring capabilities are not designed for gentle, therapeutic, neuro-modulating, sub-lethal temperature applications. Use of an electrosurgial unit requires local or general anesthetic because of its violent effect on tissues, whose temperate levels are raised to very high levels.
The present invention is directed to a modulated high frequency system for use with a signal applicator such as an electrode, conductive plate, or structure, which is applied to a patient's body to modify its neural function. The present system advantageously relieves pain or modifies a patient's neural system without average heating the patient's tissue above 45° C. to 50° C., without stimulating it at frequencies in the range of 0 to about 300 Hertz, and without burning or cauterizing it. Thus, the present system avoids the painful effects of forming radiofrequency (RF) lesions at high temperatures and circumvents the need for chronic stimulation of the tissue.
In accordance with one preferred embodiment, the system generates an RF waveform output, which is coupled to an electrode inserted into a patient's body, near or in the neural tissue. The system, by interrupting the RF waveform with bursts of RF power interposed with periods of off-time, accomplishes a pain relieving effect or other neural modulating effect in a patient, without exceeding the tissue temperature beyond approximately 45° C. on average. With this system, the painful heat lesions formed near the electrode, with temperatures substantially greater than 45° C. are avoided. The modulated RF system of the present invention may be used painlessly and easily, avoiding usual discomforts inflicted by standard RF heating procedures. Yet relief from pain or neural disfunctions such as motor disfunctions, spasticity, Parkinsonism, tremors, mood disorders, incontinence, etc., are long lasting, yielding results in many cases that are comparable to, if not superior than, results from RF heat lesions formed at much higher temperatures.
Some applications of the system and method in accordance with this invention may include relied from back, head, or facial pain, by procedures such as dorsal root ganglion or trigeminal ganglion treatments, spinal cord application for relief of intractable pain, spacicity, or motor control, treatment of the basal ganglia in the brain for relief of Parkinsonism, loss of motor control, tremors, or intractable pain. This pain relief or control of eliminator of motor or other neural disfunction is comparable if not more effective than relief from long-term stimulators with implanted electrodes. Besides, the need for permanent implants, expensive implanted devices an circuits, battery changes, involving repeated surgery and expense, and repeated application of simulation energy over long periods (months and years) is avoided.
Advantageously, unlike electrosurgical systems, the present system accomplishes pain relief or neural modification in patients in a non-violent, painless manner, avoiding average tissue temperature elevations into the lethal range and violent macroscope tissue separations.
Different embodiments of the present modulated frequency generator and its output waveforms are disclosed in this application. Some embedments with temperature monitors and thermal sensing electrodes are disclosed, which serve to control the modulated system and its use in some applications. For example, by using a temperature monitor in the tissue, to which the modulated radiofrequency output is applied, a surgeon may monitor the temperature of the tissue and thus, avoid RF voltage or current levels, which would raise the tissue to lethal thermal levels (which are generally beyond 40° C.-50° C.).
Specific processes for implementing the modulated high frequency neural modulation and the details of applying the high frequency or radiofrequency (RF) voltage, current, or power to the patient's tissue, with and without temperature monitoring to achieve desired clinical results, are described below.
In the drawings, which constitute a part of the specification, exemplary embodiments exhibiting various forms and features hereof are set forth, specifically:
Referring to
By way of an example, the signal generator element or device 5 may take the form of an RF power source with a continuous wave output. One example of such a power source is a generator identified by Model No. RFG-3C, which is available from Radionics, Inc., located in Burlington, Mass. The block indicated by reference numeral 4 is one example represents a pulse modulation unit, which switches the RF output from the signal generator 5 on and off, at a designed rate and duty cycle. Use of RF output generators or supplies and modulation circuits are known in the use of high frequency techniques (which for example, are described in a book entitled Radio Engineering by Frederick E. Terman, McGraw-Hill, New York, 1947, 3rd Edition). A temperature monitoring element or circuit 6 is also shown, which is connected by a cable 11 to the electrode and to a thermal sensor, which may be a thermistor or thermocouple, disposed inside the electrode applicator or conductive tip 1 to measure the temperature of the tissue NT near the tip. An example of such thermal sensing circuits and electrodes is one identified by Model No. RFG-3C available from Radionics, Inc., located in Burlington, Mass. Furthermore,
In operation, the voltage or current output from the signal generator 5 and the modulator 4 are impressed upon tissue NT, which may be neural tissue (for example, spinal nerves or roots, spinal cord, brain, etc.) or tissue near neural tissue. In accordance with the present invention, such an electrical output, for example, an electromagnetic output, can cause energy deposition, electric field effects, and/or electromagnetic field effects on the nerve cells in the tissue NT so as to modify or destroy the function of such nerve cells. For example, modification of neural function may include reduction or elimination of pain syndromes (such as spinal faces, mechanical back pain, facial pain) in some cases, alleviating motor disorders. Because the RF output from 5 is modulated by element 4, its percent on-time is reduced so that sustained hearing of tissue NT is reduced, yet the neural therapeutic effects of the impressed RF voltages and currents on the neural tissue NT are enough to produce the pain reducing result. The signal generator 5 may have a power, voltage, or current output control 5A (as on the Radionics Model RFG-3C RF generator) to increase or decrease the output power magnitude or modulated duty cycle to prevent excessive heating of tissue NT or to grade the level of pain interruption as clinically needed. Output control 5A may be a knob, which raises or lowers the output in a smooth, verniated way, or alternatively, it may be an automatic power control with feedback circuits. In this regard, the temperature monitor 6 provides the operator with the average temperature of tissue NT near electrode tip 1 to interactively prevent temperatures near tip 1 to exceed the range of approximately 45° C. (on average thermally lethal to tissue NT), and thus, to avoid the higher temperature ranges for the usual heat lesioning procedures described above. For example, element or circuit 6 may include feedback circuitry to change the modulation dutycycle (by, for example, longer or shorter on-times) to hold the temperature near tissue NT to below a set value (for example, 40° C. to 45° C.), illustrated by the feedback line 14 in FIG. 1. In addition, the high frequency waveform from the signal generator 5 is free from substantial components in the 0 to about 300 to 400 Hertz range (which is much lower than radiofrequencies), and this avoids the stimulation effects that are typical for stimulator system applications as described above.
As an example of a modulated RF waveform that accommodates the system of the present invention,
To give a representative example of values for parameters in an interrupted high frequency waveform as in
Variations of such waveforms are possible with the same intermittent high frequency effect for pain or neurological modification. For instance, a baseline V=0 may not pertain and a slowly varying baseline of non-zero value may be used. The time average of the signal need not be zero. The on and off switching of a high frequency signal such as in
A block or element 30 represents a signal generator, which may create a high frequency signal or periodic or non-periodic frequency. The signal generator 30 provides an input to a filter system 31, which selectively filters out frequencies that could cause unpleasant, undesired, or damaging physiological signals. The signal is then fed into a waveform shaping circuit 33, which shapes the waveform input from a block or element 32, which provides amplified modulation and/or frequency modulation and/or phase modulation control. Circuits of this type are described for instance in Radio Engineering by Terman (cited above, in a book entitled Radio Engineering by Frederick E. Terman, McGraw-Hill, New York, 1947, 3rd Edition). Additional waveform shaping may be done by elements 40 and 41, which control the amplitude of waveform and/or the duty cycle of the waveform, respectively. The resultant signal is then fed into a power amplifier 34. That is a wide band amplifier used to increase the signal to power levels appropriate for clinical use. This energy is then delivered to the patient via an electrode represented by element or block 35.
A temperature sensor or plurality of temperature sensors, represented by 36, may also be placed and connected proximate the electrode so as to insure that the temperature does not exceed desired limits. This temperature sensor signal is fed through a filter B represented by 37, which is a special filter module used to eliminate high frequency components, and thus, not to contaminate the low-level temperature signals.
The temperature signal is fed to a standard temperature measuring unit 38 that converts the temperature signal into a signal that may be used to display temperature and/or to control, in a feedback manner, either the amplitude and/or the duty cycle of the high frequency waveform. In this way, power delivery may be regulated to maintain a given set temperature. This flow is represented by block or element 39, which is simply a feedback control device. The dotted liens from element 39 to elements 40 and 41 represent a feedback connection that could either be electronic and/or mechanical. Alternatively, a person may simply operate these controls manually, based on the visual display of temperature, as for example, on a meter or graphic display readout 42.
As was explained with respect to the disclosed embodiments, many variations of circuit design, modulated high frequency waveforms, electrode applicators, electrode cannulas will be appreciated by those skilled in the art. For example, many electrodes or electrode applicators are practical, including tubular shapes, square shafts, flat electrodes, area electrodes, multiple electrodes, arrays of electrodes, electrodes with side outlets or side-issued tips, electrodes with broad or expandable or conformal tips, electrodes that may be implanted in various portions of the brain, spinal cord, interfacial space, interstitial or ventricular spaces, nerve ganglia may be considered with the system of the present invention.
The frequency range for the so-called high frequency waveforms, as shown for instance in
Mixtures of frequencies may be accomplished as discussed above. These may be mixtures of “high frequencies” (above the physiologic situation) range of (say 0 to 300 Hertz) and lower frequencies (within that stimulation range of say 0 to 300 Hertz). Thus, one skilled in the art may have both modulated high frequency and stimulation frequencies for various clinical effects, such as stimulation blockage of pain while neural modification is being applied according to the present invention.
Referring now to
A block or element 102 indicates the start of the high frequency application in which an “on” button may be pulsed, and the elevation of high frequency, voltage, current, or power (level) is started. In a case where the temperature sensor is disposed in or near the electrode applicator connected to the patient's body, the temperature monitor 103 is indicated, which may sense that temperature and monitor or read it out to the clinician. Alternatively, temperature sensing may also be conducted away from the output applicator. For instance, a separate temperature sensor may be inserted at a position located at a distance from the active RF electrode. Increasing the RF level 102 to achieve the neural modification effect (for example, pain relief for the patient) is accomplished by the electromagnetic, electric, or other aspects of the high frequency field in the presence of the neural structures. If the temperature monitor 103 shows that the temperature of the tissue is being elevated to lethal levels (from 40° C. to 50° C., for example, then the decision block or element 104 determines that if these levels are reached, a reduction of the RF power (block or element 105) may be implemented so at to reduce the temperature monitored level 103. If lethal temperature levels have not been reached, there is the option to continue with raising the RF level or to hold it static at a desired, predetermined level until the proper clinical effect has been reached. At end point of a particular RF level or time duration for the exposure indicated by element 106 may be utilized, and when an RF level or time has been reached, then the unit may be shut off, as indicated by block or element 107.
Referring to
Various configurations of electrodes may be used with this modified high frequency technique for neural modification. For example, in
Variations of the processes and configurations of the above figures are possible by those skilled in the art.
Variations of the steps in a high frequency neural modification procedure may be varied from those in
If generator 1400 in
A clinical experience has demonstrated such differences. Clinical data for a group of patients (Group A) for dorsal root ganglion lesions with a percutaneously placed electrode (such as 3600 in
Clinical data for a second group of patients, Group B, for a pulsed RF application was quite different for the same tip temperature. An identical electrode 36 with the same tip exposure geometry 3700 was inserted into the same region of the basal ganglion. In Group B, generator 1400 was a pulsed RF generator with a duty cycle of about two percent. All other conditions and clinical pain symptoms were the same for Group B as for Group A. The pulsed RF signal was applied with signal intensity to achieve an average temperature rise of 42° C. at the tip 3700 (the same as for Group A), but the result was a very significant elimination of pain for the patients in Group B, i.e., pulsed RF application, significant pain relief was achieved when the average tissue temperature near the electrode tip was held at 42° C. It is known from past experience that 42° C. is considered less than the conventional heat lesion or destruction temperature for tissue in such circumstances. For Group A, the same average tip temperature of 42° C. for a continuous RF signal application did not produce significant neural modification or pain relief. Previous literature by Cosman et al. referenced above indicates that 42° C. is a “non-lethal” or “sub-lethal” lesion temperature, on average, for continuous RF signals, i.e. 42° C. is below a heat lesion level, yet at 42° C. there is significant neural modification or pain relieving effect for pulsed RF signals, illustrating the differential effects of pulsed high frequency signal and its associated electronic fields within the tissue compared to continuous RF fields for analogous temperatures, even below lesion levels. Such differential effects could include pain relief, motor function changes (as in Parkinsonism), spaticity relief, epilepsy relief or interruption, neuro-cognitive changes, mood alternations, and so on. In the clinical example above, pain relief was achieved without any of the usual sensory loss or other side effects associated with heat lesioning at higher temperatures, which is a major advantage of the low temperature pulsed RF method.
The action of the modulated high frequency signal on neural tissue may eliminate pain while maintaining tactile, sensory, and other neurological functions relatively intact and without some of the deficits, side effects, or risks of conventional heat lesion making. Selectivity by pulsed RF fields may arise by selective deneravation of pain-carrying structures or cells (such as C fiber) compared to relatively non-destructive modification of other neural structures related to sensation, touch, motor activity, or higher level functions.
The selection of high frequency generator output parameters and the selection of electrode configurations such as size, shape, area, etc., may be interconnected to achieve a neural modification effect without excessive heating. At a given average power output of the generator as applied to the electrode adapter, a vary small, sharpened electrode may give rise to high current densities in the tissues adjacent to it, which can give rise to focal heating, lesions, thermal cell destruction, cooking, an coagulation of nearby tissue. If the electrode chosen is larger, then such elevated temperature conditions may be reduced as the current density emitting from the electrode is reduced. In a given clinical setting, to achieve the desired neuro modification effect without macroscopic average elevation of neural tissue above, for example, the lesion temperature of approximately 45° C. (degrees Celsius), it may be necessary to select the appropriate parameters for both the lesion generator output such as voltage, current, power, duty cycle, waveform, etc., in coordination with the selection of the appropriate electrode geometry (the selection box, for example, being indicated by element 1 of FIG. 1). The system of electronic signal generator combined with the appropriate signal applicator to achieve a given neuro modification may then be considered in combination and cooperation to achieve the effect for a particular clinical site or result.
In view of these considerations, as will be appreciated by persons skilled in the art, implementations and systems should be considered broadly and with reference to the claims set forth below.
Rittman, III, William J., Cosman, Eric R., Sluijter, Menno E.
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