RADIOFREQUENCY PROBE, SYSTEM AND METHOD FOR MULTIVARIANT ADAPTIVE CONTROL OF AN ABLATION PROCEDURE

Abstract

The present invention relates to a system and method for adaptive multivariate control for performing a radiofrequency (RF) ablation procedure with a power delivery device. The system includes a power source for supplying energy to a patient's body; one or more power delivery devices; two or more sensors for measuring at least two factors related to an ablation procedure, respectively; and at least one processor.The method includes the steps of: measuring at least two factors related to an ablation procedure; determining a first operating threshold based, at least in part, on a first factor; controlling a power delivery device based on the first operating threshold to create a lesion at the target site within the patient; determining a second operating threshold based, at least in part, on a second factor; switching control of the power delivery device from the first factor to the second factor; and controlling the power delivery device based on the second operating threshold to create a lesion at the target site within the patient. The present invention also relates to an RF probe configured for use with the adaptive multivariate control system and method for performing RF ablation procedures.

Description

RADIOFREQUENCY PROBE, SYSTEM AND METHOD FOR MULTIVARIANT ADAPTIVE CONTROL OF AN ABLATION PROCEDURE CROSS REFERENCE TO RELATED APPLICATIONS This application claims the benefit of U.S. non-provisional application No. 17 / 137.810, filed on December 30, 2020, the contents of which are incorporated herein by reference in their entirety. FIELD OF INVENTION The object of the present invention relates in general to the adaptive multivariate control of an ablation procedure and a radiofrequency probe, system and method for the same. BACKGROUND OF THE INVENTION Radiofrequency (RF) ablation is a treatment modality designed to thermally destroy unwanted biological tissue and is used to treat a variety of conditions, including tumors, cardiac arrhythmias, and pain. This modality treats pain by damaging a section of a nerve located between the source of pain and the brain. In other words, the damage prevents pain signals originating in the periphery of the nervous system from reaching higher-order neurological structures required for perception. In an RF ablation procedure, an RF ablation system generates and delivers radiofrequency energy to the target biological tissue. The RF ablation system includes an external radiofrequency generator, at least one needle-shaped electrode, often called a probe, and a secondary electrode. The secondary electrode may take the form of a large dispersive electrode, also known as a ground pad, which is placed on the surface of the patient's body, or a second needle-shaped electrode or probe. The probe typically has an insulated shaft with an exposed conductive tip to deliver RF energy. The ablation procedure involves placing the first electrode, or needle-shaped probe, on or near a target ablation site and placing the second electrode somewhere on or within the patient's body. The generator deposits an electrical charge on the electrode pair, and the polarity of the charge is then alternated within the RF range, that is, between 100 kHz and 1 GHz, and more specifically between 300 and 600 kHz. The alternating charge causes ions (Na+, K+, Cl-) within the tissue to move, analogous to an electrical current. Resistance to the electrical current causes frictional heating, coagulation of the cells, and the formation of a lesion that effectively denervizes the neural structure in question.Tissue temperatures below approximately 45 °C are considered non-destructive, while temperatures above 100–110 °C cause tissue vaporization, and at very high energy densities, tissue charring (i.e., carbonization of the tissue). Tissue charring is an irreversible process that limits further energy deposition and can stunt the development of the lesion (i.e., its shape and volume). RF ablation control systems typically use one of three methods to control the energy delivered to the biological tissue: power control, temperature control, or impedance control. Power control varies the electrical voltage applied to the tissue to maintain a constant RF power. Temperature control varies the RF energy delivered to the tissue to maintain a fixed, set temperature. In this case, a sensor (e.g., a thermocouple) is integrated into the probe to measure the tissue temperature. Impedance control adjusts the amount of RF energy delivered to the tissue depending on the tissue impedance (measured between the stimulation electrodes).Tissue impedance is sensitive to changes in the ablative environment (migration of surrounding conductive ions, desiccation, vaporization, carbonization) and can be used to describe lesion progression. Increasing tissue impedance generally indicates lesion formation, but excessively high impedance at the beginning of treatment makes it difficult to transfer RF energy beyond the tissue-electrode interface, thus limiting lesion development. In an impedance-controlled system, when tissue impedance increases and exceeds a certain threshold, the RF energy supply is switched off, allowing vapor to settle, and then resumed at a lower power level. The various RF control systems and probe designs used today, as described above, operate in an advanced manner and cannot optimize lesion formation because they do not adapt to the variability of the lesion site (i.e., differences in tissue composition between nerve, bone, blood, fat, etc.) and / or the changes that occur during treatment (e.g., fluid formation around the probe tip and / or thermocouple, vaporization, carbonization, etc.). For example, power-controlled and thermally controlled systems deliver constant power and a set temperature (respectively) to the tissue based on characterized standards, and do not adjust the stimulation energy in real time based on feedback from direct measurements of lesion formation (i.e., impedance, vaporization, etc.).Incidentally, impedance peaks are rarely observed during lesion formation with power and temperature control systems, suggesting that these systems do not deliver enough energy to completely damage the treated tissue. Furthermore, impedance-controlled systems do not account for the amount of time the tissue is exposed to the temperatures necessary to irreversibly destroy nerve tissue. Instead, impedance-controlled systems rely on impedance measurements that are variable and susceptible to artifacts. Therefore, the technique is continually seeking new and improved systems and methods for treating pain using RF ablation, and more particularly RF control systems, probes, and methods that are optimized to assess, adapt, and adjust to the changing tissue environment during the ablation procedure. BRIEF DESCRIPTION OF THE INVENTION The objects and advantages of the invention will be partly set out in the following description, or may be evident from the description, or may be learned through the practice of the invention. The present invention relates to a radiofrequency (RF) ablation system for performing an RF ablation procedure. The RF ablation system includes: a power source for delivering energy to a target site on a patient's body and one or more power delivery devices electrically coupled to the power source. The RF ablation system further includes two or more sensors for measuring at least two factors related to the RF ablation procedure. The RF ablation system additionally includes at least one processor configured to perform a plurality of operations.The plurality of operations includes: (i) measuring at least two factors related to the RF ablation procedure; (ii) determining a first operating threshold for the energy delivery device based, at least in part, on a first factor of the at least two factors; (iii) controlling the energy delivery device based on the first operating threshold to create a lesion at the target site within the patient; (iv) determining a second operating threshold for the energy delivery device based, at least in part, on an additional factor of the at least two factors; (v) switching control of the energy delivery device from the first factor to the additional factor; and (vi) controlling the energy delivery device based on the second operating threshold to further develop the lesion at the target site within the patient. In a particular modality, the at least two factors may include at least two of the following: power, current, voltage, impedance, tissue temperature at the target site, temperature of a coolant associated with a cooling device for the RF ablation procedure, stimulation duration (time), rate of change of current, rate of change of voltage, rate of change of power, rate of change of tissue temperature at the target site, rate of change of coolant temperature, pressure at the target site, gas formation at the target site, rate of change of gas formation at the target site, or a combination of these. In addition, one of the at least two factors may be the rate of change of tissue impedance. In another mode, the system can be configured to continuously monitor and record at least two factors. In an additional modality, the first factor can be a tissue temperature at the target site. In an additional modality, the additional factor may be the tissue impedance or the rate of change of tissue impedance at the target site within the patient. In yet another mode, the system can be configured to determine at least one additional operating threshold for the power supply device based, at least in part, on a third factor; and switch control of the power supply device from the first operating threshold or the second operating threshold to the third operating threshold lA / t / ZUZÓ / UtWZ I t to further develop the injury at the target site. In another mode, at least one of the two or more sensors can be configured to measure a respective factor related to the ablation procedure at the target site. In a further embodiment, the one or more power delivery devices may include an RF probe comprising: an elongated member having a proximal end and a distal end, the distal end comprising an electrically and thermally conductive power delivery device for delivering electrical and RF power to a patient's body, the RF probe having at least one electrode and an electrically and thermally conductive portion having a temperature sensing element; and one or more ablation enhancement features comprising: a cooling device extending within the elongated member, a suction mechanism having a suction path, a fluid injection mechanism having a fluid path, and / or a directional power delivery mechanism. In addition, the two or more sensors may include at least one thermocouple positioned on the RF probe. In one further mode, the system can be configured to switch control of the power supply device from the first factor to the additional factor after the first operating threshold is reached. The present invention further relates to a radiofrequency (RF) probe. The RF probe includes: an elongated member having a proximal end and a distal end, the distal end comprising an electrically and thermally conductive power delivery device for delivering electrical and radiofrequency energy to a target site on a patient's body, the electrically and thermally conductive power delivery device having an electrically and thermally conductive portion having at least one electrode and a temperature sensing element; and at least one ablation enhancement feature configured to enhance lesion formation when the RF probe is applied to a patient's tissue in an ablation procedure. In a particular RF probe designation, at least one electrode may be porous. Additionally, at least one ablation enhancement feature may include a suction mechanism having a suction path, where the suction path is defined by the interior of the elongated member extending from the distal to the proximal end. Furthermore, at least one ablation enhancement feature may include a fluid injection mechanism having a fluid path, where the fluid path is defined by the interior of the elongated member extending from the distal to the proximal end. In another embodiment, at least one ablation-enhancing feature may include a suction mechanism having a suction path and / or a fluid injection mechanism having a fluid path. Furthermore, the RF probe may also include an additional electrode disposed within the suction path and / or the fluid path. Additionally, the suction path may include a suction channel within the elongated member, and the fluid path comprises a fluid channel within the elongated member. In an additional modality, at least one ablation enhancement feature can be defined by the electrode being formed in a geometric shape that extends along a portion of the elongated limb so that the electrode is configured to individually target rotational sections of the patient's tissue surrounding the elongated limb. In yet another modality, at least one ablation enhancement feature may include a plurality of secondary electrodes composed of spikes extending from the elongated limb that are configured to surround an area of ​​target patient tissue in a three-dimensional orientation. In one further embodiment, the elongated member may also include one or more internal lumens to contain a refrigerant inside. The present invention further relates to a method for performing a radiofrequency (RF) ablation procedure with an RF probe. The method includes the following steps: measure at least two factors related to an ablation procedure; determine a first operating threshold for the RF probe based, at least in part, on a first factor; control the RF probe based on the first operating threshold to create a lesion at a target site within the patient; determine a second operating threshold for the RF probe based, at least in part, on a second factor; Switch the RF probe control from the first factor to the second factor; and control the RF probe based on the second operating threshold to further develop the lesion at the target site within the patient. In one particular mode, the stage of switching the RF probe control from the first factor to the second factor can occur after the first operating threshold is reached. In another modality, the method may also include the following stages: collect data related to the operation of the RF probe during the measurement stages, determination of the first and second operating thresholds, control and switching; lA / t / ZUZÓ / UtWZ I t introduce the collected data into a deep learning network configured to learn the measurement, determine the first and second operating thresholds, control and switch the stages related to the RF ablation procedure; and control the RF probe based on the deep learning network. These and other features, aspects, and advantages of the present invention will be better understood with reference to the following description and the accompanying claims. The accompanying figures, which are incorporated herein and form part of this specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention. BRIEF DESCRIPTION OF THE FIGURES A complete and enabling description of the present invention, including the best embodiment thereof, addressed to a person skilled in the art, is set forth in the descriptive memorandum, which refers to the accompanying figures, in which: Figure 1 illustrates a diagram of a radiofrequency (RF) ablation system according to a particular modality of the present invention. Figure 2 illustrates a cross-sectional view of the active tip of one modality of an RF probe configured for use with the system in Figure 1. Figure 3 illustrates a perspective cross-sectional view of the active tip of another modality of an RF probe configured for use with the system in Figure 1 that has cooling fluid inlet and outlet channels. Figure 4A illustrates a cross-sectional view of one modality of an active tip of the RF probe of Figure 2. Figure 4B illustrates a cross-sectional view of the active tip of Figure 4A taken along line 4-4. Figure 5A illustrates a cross-sectional view of one modality of an active tip of the RF probe of Figure 2. lA / t / ZUZÓ / UCW / I t Figure 5B illustrates a cross-sectional view of the active tip of Figure 5A taken along line 5-5. Figure 6 illustrates a perspective view of another modality of an active RF probe tip that has a directional power delivery mechanism. Figure 7 illustrates a perspective view of another modality of an active RF probe tip that has one or more secondary electrodes extending from the elongated member. Figure 8 illustrates a system diagram of a pump assembly according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION The following will refer in detail to embodiments of the invention, one or more examples of which are illustrated in the drawings. Each example is provided by way of illustrative of the invention, not as a limitation thereof. In fact, it will be evident to persons skilled in the art that various modifications and variations of the present invention may be made without departing from the scope or spirit of the invention. For example, features illustrated or described as part of one embodiment may be used with another embodiment to produce yet another embodiment. The present invention is therefore intended to cover such modifications and variations, which are included within the scope of the appended claims and their equivalents. Before explaining at least one embodiment of the invention in detail, it should be understood that the invention is not limited in its application to the details of the construction and arrangement of the components set forth in the following description or illustrated in the drawings. The invention may have other embodiments or may be practiced or carried out in various ways. Furthermore, it should be understood that the phraseology and terminology employed herein are for descriptive purposes and should not be considered limiting. For the purposes of this invention, an injury refers to the region of tissue that has been irreversibly damaged as a result of the application of thermal energy, and the invention is not intended to be limited to this respect. Furthermore, for the purposes of this description, proximal generally indicates the portion of a device or system near or closer to a probe handle (when the device is in use), while the term distal generally indicates a portion farther from the probe handle (when the device is in use). As used herein, the terms “approximately” or “generally,” when used to modify a value, indicate that the value may be increased or decreased by 5% and remain within the disclosed range. Furthermore, when a plurality of ranges are provided, the present invention contemplates any combination of a minimum and a maximum value described within the plurality of ranges. For example, if ranges of “approximately 20% to approximately 80%” and “approximately 30% to approximately 70%” are described, the present invention also contemplates a range of “approximately 20% to approximately 70%” or a range of “approximately 30% to approximately 80%.” In general terms, the present invention relates to a system and method for adaptive multivariate control for performing a radiofrequency (RF) ablation procedure with an RF probe. The system includes a power source for supplying energy to a patient's body; one or more power delivery devices electrically coupled to the power source; two or more sensors for measuring at least two factors related to an ablation procedure, respectively; and at least one processor configured to perform a plurality of operations to control an RF ablation procedure.The method includes the steps of: measuring at least two factors related to an ablation procedure; determining a first operating threshold for the RF probe based, at least in part, on a first factor; controlling the RF probe based on the first operating threshold to create a lesion at the target ablation site within the patient; determining a second operating threshold for the RF probe based, at least in part, on a second factor; switching the control of the RF probe from the first factor to the second factor; and controlling the RF probe based on the second operating threshold to create a lesion at the ablation site within the patient. The present invention also relates to an RF probe and an RF ablation system configured for adaptive multivariate control.The present inventors have discovered that adaptive multivariate control of RF ablation, such as the use of the control system, probe, and method of the present invention, allows for the optimization of lesion formation during the ablation of biological tissue. In particular, adaptive multivariate control of RF ablation allows the ablation procedure to "listen" to the tissue at the target site, especially to the changing conditions of the tissue at the target site, to determine how to direct and control the delivery of RF energy to the target site. The specific features of the RF ablation probe, system, and method of the present invention can be better understood with reference to Figures 1-8. With reference to the drawings, Figure 1 illustrates a schematic diagram of one embodiment of a system 100 of the present invention. As shown, the system 100 includes a controller 110, a generator 120, and at least one power supply probe 200. The system further includes at least one secondary electrode, for example, the grounding pad 300 as depicted in Figure 1, or a second probe 200 (not shown). The system 100 may optionally include one or more cooling devices 130, a suction device 140, and a fluid injection device 150. Additionally, in aspects of the invention, more than one probe 200 may be present in the system 100.As shown in the illustrated version, the 120 generator is a radio frequency (RF) generator, but it can optionally be any power source for a delivery device that can supply other forms of energy, including, but not limited to, microwave energy, thermal energy, ultrasound, and optical energy. In addition, the 110 controller and / or the 120 generator may include a built-in display. The display may be operable to show various aspects of a treatment procedure, including, but not limited to, any parameters relevant to the treatment procedure, such as temperature, impedance, etc., and errors or warnings related to the treatment procedure. If no display is incorporated into the 110 controller and / or the 120 generator, the 110 controller and / or the 120 generator may include means for transmitting a signal to an external display.In one mode, the controller 110 can be operated to communicate with one or more devices, for example, with one or more power supply probes 200 and the generator 120, the cooling device 130, the suction device 140, and / or the fluid injection device 150. Such communication can be unidirectional or bidirectional depending on the devices used and the procedure performed. The controller 110 may include a processor 112, a memory device 114 that stores one or more control algorithms 115, and a user input 116, such as a control button, touchscreen, or other user input. The energy delivery probes 200 may include any means of delivering energy to a target tissue region 20 of a patient's body 10 adjacent to the distal tip region 218. For example, the probes 200 may include an ultrasonic device, an electrode, or any other means of energy delivery, and the invention is not limited in this respect. Similarly, the energy delivered through the probes 200 may take various forms, including, but not limited to, thermal energy, ultrasonic energy, radiofrequency energy, microwave energy, or any other form of energy. For example, in one modality, the active region 218 of the probes 200 may include an electrode 241.As described in more detail below with reference to Figures 2-3, the active region 218 of the electrode can be from 2 to 20 millimeters (mm) in length, and the energy supplied by the electrode is electrical energy in the form of current in the RF range. The size of the active region 218 of the electrode can be optimized for placement in a specific anatomical location 20, such as within an intervertebral disc; however, different sizes of active regions can be used, all of which are within the scope of the present invention, depending on the specific procedure being performed. In some modalities, feedback from the generator 120 can automatically adjust the exposed area, i.e., the active region or tip 218, of the probes 200 in response to a given measurement, such as impedance or temperature.For example, in one mode, the 200 probe can maximize the energy delivered to the tissue by implementing at least one additional feedback control, such as an increasing impedance value. With reference to Figures 1-2, a specific embodiment of a radio frequency power supply probe 200 of the present invention is shown in greater detail. As shown, the probe 200 includes a handle 212, an elongated member 210, and a cable tube assembly 220. The cable tube assembly 220 can communicate with the handle 212 at one end of the handle 212. The elongated member 210 can communicate with the handle 212 at an opposite end of the handle 212. As depicted in Figure 1, the cable tube assembly 220 includes an electrical cable 222 and, optionally, a fluid tube 224 in communication with a fluid injection device 150 and / or a cooling device 130 that recirculates cooling fluid. The 222 electrical cable may include an insulating jacket constructed of, for example, polyvinyl chloride (PVC) or any other suitable material.The electrical cable 222 may terminate at one proximal end in an electrical connector 223. The electrical connector 223 may be, for example, a circular electrical connector as depicted in Figure 2, configured to be placed in electrical communication with an electrical connection of the generator 120. The fluid tube 224 may be constructed from one or more lumens, such as double lumens having walls constructed from transparent polyvinyl chloride (PVC). The walls of the double lumen tube may optionally be thermally bonded together. The double lumen fluid tube 224 may terminate at one proximal end in a connector 226, such as a female or male Luer connector. Additionally, a cap, for example, a vented cap (not shown), may be provided to cover or seal the connector 226. The cap may be made of nylon or another suitable material and may have a different color or opacity than the connector 226. The cable tube assembly 220 can be flexible due to the flexible materials of the electrical cable's insulating sheath 222 and the lumen walls 224. The cable tube assembly 220 can optionally be joined between the electrical cable's insulating sheath 222 and the wall of at least one lumen of the fluid tube 224 along the length of the assembly 220. The joining can be made, for example, by thermal welding, UV adhesive, or any other suitable method of welding or joining plastic or polymeric materials together. Figure 2 further illustrates the active tip 218 of the elongated member 210 of the probe 200. The elongated member 210 has an active tip 218 configured for RF power delivery located at a distal end thereof. In particular, an electrode 241 can be formed on the active tip 218. A lumen 214 is formed within the elongated member 210 that extends along the length of the elongated member 210. The elongated member 210 includes a thermocouple hypotube 240 that extends along the length of the elongated member 210 and has a wire 242, such as a constantane wire, extending through it. The constantan wire 242 can form a thermocouple 247 at the distal end of the active tip 218 of the elongated member 210, and extend through the elongated member 210 to the electrical wire 222 to sense the temperature at the active tip 218 and transmit temperature information to the controller 110.Wire 242 can be soldered to the thermocouple hypotube 240 at the distal end 218 of the elongated limb 210 to form a thermocouple 247. The thermocouple 247 can function as a temperature-sensing element to detect the patient's tissue temperature and the temperature of the active distal tip 218 of the elongated limb 210. Optionally, as depicted in Figure 2, the elongated limb 210 can include a distal opening 244 and / or one or more openings 290 in fluid communication with the lumen 214. The distal opening 244 and / or the openings 290 allow for suction and / or delivery of fluid to or from the target area 20, for example, when the probe 200 is in communication with a fluid injection device 150 and / or a suction device 140. Figure 3 illustrates a perspective cutaway view of the active tip 218 of the elongated member 210 of the probe 200 in another embodiment of the invention, where the probe 200 is a cooled probe cooled by fluid circulation within the elongated member 210. As with the probe 200 illustrated in Figure 2, the elongated member 210 includes a thermocouple hypotube 240 extending along the length of the elongated member 210 and having a wire 242 extending through it. The tube 240 may be made of, for example, stainless steel or another suitable material. The wire 242 may be constantan wire. The wire 242 may be a solid wire or a porous wire, as will be described in more detail below. When cable 242 is porous, lA / t / ZUZÓ / UCW / I t forming a porous electrode 241, the electrode 241 may include a distal opening 244.Wire 242 can be soldered to the thermocouple hypotube 240 at the distal end 218 of the elongated member 210 to form a thermocouple 247. The thermocouple 247 can extend beyond the distal end 218 of the elongated member 210. Furthermore, the length of the thermocouple 247 can be selected to help create lesions of different sizes. For example, in such modalities, a user can select one or more probes from a plurality of probes having different lengths based on, for example, a desired lesion size and / or a desired energy delivery rate depending on a type of tissue treatment procedure. In particular modalities, the length of the thermocouple 247 is less than approximately 1 mm; for example, the length of the thermocouple 247 can vary from approximately 0.20 mm to approximately 0.70 mm. In some aspects of the invention, the thermocouple 247 can also have a different shape or volume.Therefore, since the actual size of the lesion will vary with the lengths of the 247 thermocouple, a 247 thermocouple that has a longer length can be configured to generate smaller lesions, while a 247 thermocouple that has a shorter length can be configured to generate larger lesions. Therefore, varying the length of thermocouple 247 can control and optimize lesion size for different anatomical locations, for example, by creating smaller lesions in regions adjacent to critical structures such as arteries and motor nerves. Thus, the range of thermocouple 247 lengths described herein provides several advantages, including the ability to create customized lesion volumes for different procedures (i.e., lesion volume control is intrinsic to the probe's mechanical design, independent of the generator and algorithms). Furthermore, the varying lengths of thermocouple 247 create a mechanical safety mechanism to prevent over-ablation in sensitive anatomical regions. Furthermore, the length of the thermocouple 247 is configured to increase (or decrease) the power demand of the extended member 210. Additionally, as shown, the thermocouple 247 includes a stainless steel hypotube 240, which is electrically conductive and can be electrically coupled to the extended member 210 to form the electrode 241. Placing the thermocouple 236 at the distal active tip 218, rather than within a lumen or volume 214 defined by the extended member 210, can be advantageous because it allows the thermocouple 247 to provide a more accurate indication of the tissue temperature near the distal tip 218. This is because, when extended beyond the distal tip 218, the thermocouple 247 will not be as affected by the coolant flowing within volume 214 as it would be if it were located within volume 214.Therefore, in such modalities, the probe 200 may include a protrusion formed by the distal tip 218 protruding from the distal region of the elongated limb 210, so that the protrusion is a component of the thermocouple 247. In one embodiment, the thermocouple 247 is connected to the generator 120 and / or the controller 110 via cable 222 of the cable tube assembly 220, although any means of communication between the thermocouple 247 and the generator 120 and / or the controller 110, including wireless protocols, are included within the scope of the present invention. Figure 3 further illustrates a fluid inlet tube 232 and a fluid return tube 234 extending within the elongated member 210 to the distal active tip 218. The fluid inlet tube 232 is configured to circulate cooling fluid from the cooling device 130 to the distal active tip 218, where the fluid can flow into the inner lumen 214 of the elongated member 210 and be returned through the return tube 234 to the cooling device 130. The fluid inlet tube 232 and the fluid return tube 234 are attached to the fluid tube 224 using connecting means (not shown) to form a fluid-tight seal. The connecting means can be any two-tube connecting means, including, but not limited to, ultraviolet (UV) glue, epoxy, or any other adhesive, as well as a friction or compression fitting.For example, tubes 232 and 234 can be attached to fluid tube 224 using medical-grade adhesives (not shown). With reference still to Figure 3, the probe 200 may further include one or more secondary temperature-sensing elements 270 located within the elongated member 210 at a distance from the distal tip 218, and positioned adjacent to a wall of the elongated member 210. The secondary temperature-sensing elements 270 may similarly include one or more thermocouples, thermometers, thermistors, optical fluorescent sensors, or any other temperature-sensing means. For example, as shown, the secondary temperature-sensing element 270 is a thermocouple made by joining copper and constantan thermocouple wires, designated as 274 and 276 respectively. Furthermore, in certain embodiments, the copper and constantan wires 274 and 276 may extend through a lumen of the elongated member 210 and may be connected to the electrical wire 222 of the cable tube assembly 220. Furthermore, the probe 200 may also include a thermal insulator 272 located close to any of the temperature sensing elements 270. As such, the thermal insulator 272 may be made of any thermally insulating material, for example, silicone, and may be used to isolate any temperature sensing element from other components of the probe 200, so that the temperature sensing element can more accurately measure the temperature of the surrounding tissue. More specifically, as shown, the thermal insulator 272 is used to isolate the temperature sensing element 270 from the cooling fluid passing through the fluid inlet tube 232 and the fluid return tube 234. In some embodiments of the invention, one or more secondary temperature-sensing elements 270 may be the only temperature-sensing elements, and the thermocouple 247 at the distal end 218 may be omitted from the probe 200. For example, in embodiments where the probe 200 is intended to be able to come into contact with bone (i.e., bone tissue or periosteum), one or more temperature-sensing elements 270 along the probe 210 may be beneficial. Conversely, a thermocouple 247 at the distal end 218 of the probe 200 cannot touch the bone, so a user cannot definitively confirm through direct contact that the probe 200 is in a stable position and ready for administration without falling out. However, positioning one or more temperature-sensing elements 270 along the length of the extended member 210 can eliminate such potential problems. In additional embodiments, the elongated member 210 of the probe 200 may also include a radiopaque marker 280 incorporated somewhere along the elongated member 210. For example, as depicted in Figure 3, an optimal location for a radiopaque marker may be in or near the distal tip region 218. Radiopaque markers are visible on fluoroscopic X-ray images and can be used as visual aids when attempting to precisely position devices within a patient's body. These markers may be made of many different materials, provided they possess sufficient radiopacity. Suitable materials include, but are not limited to, silver, gold, platinum, and other high-density metals, as well as radiopaque polymeric composites. Various methods may be used to incorporate radiopaque markers in or on medical devices, and the present invention is not limited in this respect. Figures 4A-B and 5A-B illustrate embodiments of the elongated member 210 having a porous electrode 241 and a solid wire electrode 241, respectively. Figure 4A shows a side-sectional view of the elongated member 210 having a porous electrode 241 within a hollow space 248 of the hypotube 240. The porous electrode may be formed from a wire mesh and / or braided wire or may be an open-coil electrode formed as a loosely wound helix. Figure 4B shows a cross-sectional view of the elongated member of Figure 4A taken along line 4-4, illustrating the hypotube 240 within the internal lumen 214 of the elongated member 210. The porous electrode may be disposed within the hollow space 248 of the hypotube 240. As depicted in Figure 4A, there may be an opening 244 in the hypotube 240 at the distal end.Such an arrangement shown in Figure 4A-B may allow a suction device 140 and / or a fluid injection device 150 to suction and / or inject fluid directly through the tube 240 by supplying and / or removing fluid through the hollow space 248. The suction device 140 and the fluid injection device 150 are each ablation enhancement features that are configured to assist in the further development of a lesion in the patient's tissue during an ablation procedure. Figures 5A-B illustrate embodiments of the elongated limb 210 having a solid wire electrode 242. Figure 5A shows a side-sectional view of the elongated limb 210 having a solid wire electrode 242 within the hypotube 240. The hypotube 240 may further include a suction channel 250 and / or a fluid injection channel 260 configured to suction and / or deliver fluid to the patient tissue through an opening 244 at the end of the hypotube 240. In this respect, both suction and fluid injection could be performed within the same procedure, for example, simultaneously or in an alternating arrangement. lA / t / ZUZÓ / UCW / I t For example, a suction device 140 can be provided that is in communication with the suction channel 250 of the probe 200, for example, via a suction connector 228 and the controller 110 of system 100. By providing a suction device 140 that includes a suction path within the elongated limb 210, as described above, fluids (liquids and gases) can be diverted away from the conductive surface of the ablation electrode 241. By directing fluids and gases away from the conductive surface of the ablation electrode 241, the variability of the energy delivered from the electrode 242 to the tissue can be reduced. The suction device 140 can further include one or more sensors (not shown) for monitoring the suction pressure and / or the pressure within the lumen 214 of the elongated limb 210 and in the target area 20 of the tissue. The suction device 140 of the present invention may further include one or more electrodes (not shown) arranged within the suction path, for example, within the hypotube 240 or within a suction channel 250, if present. The electrode or electrodes within the suction path can assist the system 100 in monitoring the presence of vapor at the lesion site and assessing the degree of lesion formation. By assessing the degree of lesion formation, the electrode or electrodes within the suction path can function as an ablation enhancement feature. In particular, the system 100 can compare the impedance values ​​measured using the electrode 242 with the impedance values ​​measured by an electrode within the suction path to determine lesion integrity.If the ablation electrode 242 has a lower impedance value than the impedance measured by an electrode within the suction path, then the lesion is incomplete. If the impedance values ​​of both the ablation electrode 242 and an electrode within the suction path are high, then the lesion is complete. Because the integrity of the lesion can be monitored, the total ablation time can be reduced if the lesion is determined to be complete. In another aspect of the present invention, as depicted in Figure 6, the probes 200 may include a directional energy delivery mechanism formed by a directional electrode 241. For example, the electrode 241 may be formed in a geometric shape extending along a portion of the elongated member 210, such as a longitudinal strip along the elongated member 210. As depicted in Figure 6, the electrode 241 may extend along a portion of the elongated member 210 at the active tip 218, where the electrode 241 is exposed beneath an insulating layer 243 surrounding the elongated member 210. In this configuration, the electrode 241 may be configured to individually target rotational sections of patient tissue surrounding the elongated member 210 as the elongated member 210 rotates within the target area 20 during an ablation procedure.Since energy is not delivered to the target area 20 all at once, tissue vaporization is localized, and vapor can drift into the immediately adjacent tissue that has not yet been injured. Using electrode 241, tissue impedance can be measured at each rotational position to ensure that maximum injury has formed around the elongated limb 210 of probe 200. As a result, manipulation of the directional electrode 241 can be used to ensure uniform 360-degree injury around the electrode despite any local differences in tissue properties. Because the energy from the directional electrode 241 can be focused on one rotational region of the injury at a time, different amounts of energy can be delivered to each rotational region to ultimately ensure similar tissue impedance measurements and injury consistency in each rotational region. lA / t / ZUZÓ / UCW / I t In a further aspect of the invention, as depicted in Figure 7, the elongated member 210 of a probe 200 may include a first electrode 241 at the distal active tip 218 of the elongated member 210 and one or more secondary electrodes 245 extending from the elongated member 210. For example, the one or more secondary electrodes 245 may extend from the distal end 218 of the elongated member 210. As depicted in Figure 7, the secondary electrodes 245 may be in the form of two or more teeth 245 configured to surround the target area 20 in a three-dimensional orientation. The teeth 245 can be straight or have an angled or curved configuration, as depicted in Figure 7. In such an arrangement, RF energy can be pulsed back and forth between each of the teeth 245 and / or pulsed between one or more of the teeth 245 and the first electrode 241.Each of the electrodes 241 and 245 can be configured to supply RF energy and measure biological factors in the target area 20, e.g., tissue temperature and tissue impedance, in an independent manner. As described above, the system 100 may include a cooling device 130 configured to reduce the temperature of the material located in and near one or more of the probes 200. For example, the cooling device 130 may include circulating a cooling fluid through the elongated member 210, such as by circulating a fluid through the inlet tubes 232 and outlet tubes 234 via one or more pumps (not shown). Additionally or alternatively, the cooling device 130 may include a heat transfer material and / or a heat sink disposed within the elongated member 210. For example, a heat sink may include a phase-change material.In one particular embodiment, approximately 1 gram to approximately 12 grams of the phase-change material may be required to remove approximately 2 watts to approximately 12 watts of power from probe 200 over a period of 150 seconds. An exemplary phase-change material may comprise paraffin wax. In alternative arrangements, a heat sink may include a heat sink external to probe 200 and / or an endothermic reaction system. The cooling device 130 may additionally or alternatively include a heat transfer material such as a thermally conductive material, for example, a metal, a ceramic material, or a conductive polymer, or one or more Peltier circuits. As described above, the system 100 may additionally include a fluid injection device 150, for example, by administering fluid through the elongated limb such as through a fluid injection channel 260. In contrast to the cooling device 130, which circulates fluid within the probes 200 to cool the probes and the tissue at the injury site, the fluid injection device 150 can deliver fluid through the probe 200 to the patient's tissue at the injury site, for example, through the opening 244 in the tip of the electrode 241. The fluid injected at the injury site can cool the injury site near the electrode 241, thereby allowing higher currents to pass to the more distal tissue and the injury to grow before any vaporization or desiccation occurs near the electrode 241.Furthermore, if a highly conductive fluid is introduced through the 150 fluid injection device, it can contribute to lesion formation and deactivate nearby nerve cells through ionic and osmotic imbalance. The delivered fluid can displace vapor pockets and penetrate desiccated tissue regions, thereby aiding RF energy delivery and lesion site expansion. In one modality, the system 100 may include a first and a second probe 200 and may be operated in bipolar mode. In such modalities, electrical energy is supplied to the first and second probes 200, and this energy is preferably concentrated between them through a region of tissue to be treated. The region of tissue to be treated is thus heated by the energy concentrated between the first and second probes 200. In other modalities, the first and second probes 200 may be operated in monopolar mode, in which case a grounding pad 300 is required on the surface of a patient's body 10, as known in the art. Any combination of bipolar and monopolar procedures may also be used. It should also be understood that the system may include more than two probes 200.For example, in some modes, three 200 probes can be used and the 200 probes can be operated in a three-phase mode, so the phase of the current supplied differs for each 200 probe. In additional embodiments, the system can also be configured to control one or more aspects of the current flow between electrically conductive components and the current density around a particular component. For example, a system 100 of the present invention may include three electrically conductive components, including two of similar or identical dimensions, e.g., two probes 200, and a third of a larger dimension, e.g., a grounding electrode 300, sufficient to act as a dispersive electrode. Each of the electrically conductive components must be operable to effectively transmit energy between a patient's body 10 and a power source 120. Therefore, two of the electrically conductive components may be probe assemblies 200, while the third electrically conductive component may function as a grounding pad 300 or a dispersive / return electrode.In one embodiment, the dispersive electrode 300 and a first probe 200 are connected to the same electrical pole, while a second probe is connected to the opposite electrical pole. In this configuration, the electrical current can flow between the two probes or between the second probe and the dispersive electrode. To control whether the current preferentially flows to the first probe assembly or to the dispersive electrode, a resistance or impedance can be varied between one or more of these conductive components (i.e., the first probe and the dispersive electrode) and a current sink (e.g., the circuit's "ground").In other words, if it is desirable to have current flow preferentially between the second probe and the dispersive electrode (as in a monopolar configuration), then the resistance or impedance between the first probe and the "ground" circuit can be increased so that the current will preferentially flow through the dispersive electrode to ground rather than through the first probe (since electric current preferentially follows a path of least resistance). This can be useful in situations where it would be desirable to increase the current density around the second probe assembly and / or decrease the current density around the first probe.Similarly, if it is desirable to have a preferential current flow between the second probe and the first probe (as in a bipolar configuration), then the resistance or impedance between the dispersive electrode and ground can be increased so that the current will preferentially flow through the first probe assembly to ground rather than through the dispersive electrode. This would be desirable when a standard bipolar lesion needs to be formed. Alternatively, it may be desirable to have a certain amount of current flow between the second probe and the first probe, with the remainder of the current flowing from the second probe to the dispersive electrode (a quasi-bipolar configuration). This can be achieved by varying the impedance between at least one of the first probe assembly and the dispersive electrode, and ground, so that more or less current will flow along a desired path.This would allow a user to achieve a specific desired current density around a probe. Therefore, this feature of the present invention can enable a system to alternate between monopolar, bipolar, or quasi-bipolar configurations during a treatment procedure. lA / t / ZUZÓ / UtWZ I t Still referring to Figure 1, the system 100 may include a controller 110 and a processor 112 to facilitate communication between the cooling device 130, the suction device 140 and / or the fluid injection device 150 and the generator 120. In this way, feedback control is established between the generator 120 and the cooling device 130, the suction device 140, and / or the fluid injection device 150. The feedback control may include the generator 120, the probe 200, and the suction device 140, and / or the fluid injection device 150, although any feedback between two devices is within the scope of the present invention. The feedback control may be implemented, for example, in a control module that may be present independently of the generator 120, as depicted in Figure 1, or alternatively, it may be a component of the generator 120.In such modalities, the generator 120 is operable to communicate bidirectionally with the probe 200, as well as with the cooling device 130, the suction device 140 and / or the fluid injection device 150. In the context of this invention, bidirectional communication refers to the ability of a device to receive a signal from and send a signal to another device. As an example, controller 110 can receive one or more temperature measurements from probe 200. Based on these temperature measurements, generator 120 can perform an action, such as modulating the power sent to probe 200. Therefore, each probe 200 in system 100 can be individually controlled based on its respective temperature measurements. For example, the power to each probe 200 can be increased when a temperature measurement is low or decreased when a measurement is high. This power variation may be different for each probe 200. In some cases, the generator 120 may terminate the power supply to one or more probes 200. Therefore, the controller 110 may receive a signal (e.g., temperature measurement) from one or more probes 200, determine the appropriate action, and send a signal (e.g., power decrease or increase) through the generator 120 back to the one or more probes.Alternatively, controller 110 can send a signal to cooling device 130 to increase or decrease the degree of cooling supplied to each probe 200. When more than one probe 200 is used, the average or maximum temperature of the temperature sensing elements associated with the probe 200 can be used to modulate the cooling. In other modes, cooling device 130 can reduce the cooling rate or decoupling depending on the distance between multiple probe 200 assemblies. Cooling device 130 can also communicate with controller 110 to alert controller 110 to one or more potential errors and / or anomalies associated with the cooling device 130.For example, if the cooling flow is blocked, the 110 controller can then act on the error signal by at least one of alerting a user, aborting the procedure, and modifying an action. The present invention further relates to an adaptive multivariate control system and method for the RF ablation system 100. For example, the control system can initiate an ablation procedure by controlling the power supply and / or cooling based on a factor (e.g., power control, temperature control, or impedance control). Meanwhile, one or more sensors in the probe 200 and / or the controller 110 continuously monitor a plurality of characteristics of the RF ablation procedure, including, but not limited to, tissue temperature at the target ablation site, supplied power (voltage), current, impedance, stimulation time, cooling characteristics (e.g., cooling fluid flow rate) for cooled probes, or a combination thereof.For example, a combined set of features that can be monitored is the rate of change of the IA / t / ZUZÓ / UCW / It impedance over time during RF ablation. The control system can then switch to track and control the energy delivery based on a different feature to further develop the lesion. The decision to switch between control factors is informed by the continuous monitoring of each feature and the combination thereof. The control system can autonomously make the decision to switch between control factors using algorithms 115 stored in memory device 114. Alternatively, the decision to switch between control factors can be user-directed, for example, via user input 116. In an RF ablation procedure, the radiofrequency probe system 100 and probes 200 are prepared for use in treating a patient's body tissue. For example, preparing the radiofrequency system 100 and probes 200 for tissue treatment may include determining a desired lesion size (or volume) and / or an initially required energy delivery rate. The probes 200 are then inserted into and positioned in the patient's body. More specifically, the elongated limb(s) 210 of each probe 200, each having an active energy-delivery distal tip 218, are inserted into the patient's body, and the active distal tip 218 of each elongated limb(s) 210 is directed at the target tissue 20 of the patient's body.For example, in one modality, with a patient lying on a radiolucent table, a fluoroscopic guide can be used to percutaneously insert an introducer with a stylet to access the posterior aspect of an intervertebral disc. In addition to fluoroscopy, other aids, including but not limited to impedance monitoring and tactile feedback, can be used to assist a user in positioning the introducer or probes within the patient's body. The use of impedance monitoring has been described herein, whereby a user can distinguish between tissues by monitoring impedance as a device is inserted into the patient's body. Regarding tactile feedback, different tissues may offer varying amounts of physical resistance to an insertion force.This allows a user to distinguish between different tissues by feeling the force required to insert a device through a given tissue. A second introducer with a stylet can then be placed contralaterally to the first introducer in the same manner, and the stylets are withdrawn. Thus, the probes 200 can be inserted into each of the two introducers by placing the electrodes 246 in the tissue at appropriate distances, such as from approximately 1 mm to approximately 55 mm. The RF ablation procedure further involves attaching a power source (e.g., the generator 120) to the probe(s) 200. Once in place, a stimulating electrical signal can be delivered from any of the electrodes 246 to a dispersive electrode or to the other electrode 246. When the ablation procedure is used to treat chronic pain, for example, in a spinal disc, this signal can be used to stimulate the sensory nerves where replication of symptomatic pain would verify that the disc is causing the pain. Furthermore, since the probes 200 can be connected to the RF generator 120 as well as a cooling device 130, the RF ablation procedure can include the simultaneous activation of the cooling device 130 and the delivery of power from the RF generator 120 to the tissue via the elongated limbs 210.In other words, radiofrequency energy is supplied to the electrodes 242 and the power is altered according to the temperature measured by the temperature sensing element 247 at the tip of the electrodes 242 in such a way that a desired temperature is achieved between the distal tip regions 218 of the two probes 200. lA / t / ZUZÓ / UCW / I t During the procedure, a treatment protocol such as the cooling supplied to the probes 200 and / or the power delivered to the probes 200 can be adjusted and / or controlled to maintain a desirable shape, size, and uniformity of the treatment area. More specifically, the RF ablation procedure includes actively controlling the energy delivered to the tissue, such as by controlling both the amount of energy delivered through the electrodes 242 and by individually controlling the cooling device 130, the suction device 150, and / or the fluid injection device 140, if present. In additional modes, the generator 120 can control the energy delivered to the tissue based on the measured temperature, as measured by the temperature sensing elements 247 and / or impedance sensors. More specifically, as depicted in Figure 8, a block diagram of one modality of a treatment procedure method 600 is shown, which utilizes an adaptive multivariate control method to control the radiofrequency ablation procedure according to the present invention. For example, in method 600, two variables are used to control the procedure. The RF ablation procedure can begin by supplying energy to achieve a set temperature. Then, the control system can switch to controlling the energy supply based on the rise or peak of the tissue impedance (i.e., the rate of change of impedance). For example, the control system can switch to control based on the rate of change of impedance after the set temperature has been reached.All other features of the RF ablation treatment are continuously recorded and monitored as shown in 606, so that the control system can take real-time action to increase, decrease, or turn off the power supply through probe 200. As shown in 602, initial settings (i.e., a setpoint) for temperature, pulse width of delivered energy, and duration are entered, for example, via user input 116. Operating thresholds for the first factor, e.g., temperature, and the second factor, e.g., impedance, can also be entered during step 602. As shown in 604, the output power of generator 120 for energy delivery is started to supply energy through probes 200. As shown in 606, two or more factors or characteristics related to the ablation procedure are continuously monitored and recorded.These factors may include, but are not limited to, one or more of the following: energy supplied, power (voltage), current, tissue impedance, stimulation time, rate of change of tissue impedance, tissue temperature, coolant temperature, and coolant flow rate. In the first treatment phase 610 of method 600, the controller 110 controls the energy supply through the probe(s) 200 to modulate a first factor, e.g., temperature. In 612, the first and second factors, e.g., tissue temperature and tissue impedance, are measured to determine whether they have stabilized. Then, in 614, the measurement of the first factor is compared to the first operating threshold set in 602 to determine whether the first operating threshold has been reached. If the first operating threshold is not reached, then the energy supply is increased or decreased, as shown in 616.The first treatment phase 610 continues until the first operating threshold has been reached. Then, in 618, the measurement of the second factor, for example, impedance, is compared with the second operating factor to determine if the second operating factor is stabilized, i.e., not changing. If so, the control method then proceeds to the second treatment phase 620, in which the power supply is managed to modulate the second factor, for example, impedance. In the second treatment phase 620, the second factor, for example, the IA / t / ZU / UCW / It impedance, is monitored and compared with the second operating threshold as shown in 624. If the second operating threshold has not been reached, the supplied power is increased in 622. The second treatment phase 620 continues until the second operating threshold, for example, a specific impedance value or impedance change rate, has been reached. Finally, in 630, the treatment ends and the output power is switched off. Although a modality of method 600 has been previously described in which temperature and impedance are used in the adaptive multivariate control of a radiofrequency ablation procedure, it should be understood that the adaptive multivariate control contemplated by the present invention may implement controls based on two or more of supplied energy, power (voltage), current, impedance, stimulation time, rate of impedance change, temperature, coolant temperature, and coolant flow rate, or combinations thereof. Furthermore, the 600 method can also include developing and training a tissue lesion deep learning network—that is, using artificial intelligence—to automatically adapt the energy delivery for tissue ablation to a changing tissue environment. For example, in several modalities, the 100 system is configured to train the deep learning network to automatically learn the method steps related to multivariate control and the operation of the 200 probe based on a changing tissue environment. In one modality, the deep learning network can be trained offline. More specifically, the 112 processor feeds the collected data into the deep learning network, which is configured to learn the steps related to multivariate control and the operation of the 200 probe based on a changing tissue environment during lesion formation.In addition, treatment patterns can be fed into the deep learning network. lA / t / ZUZÓ / UCW / I t As used herein, the deep learning network may include one or more deep convolutional neural networks (CNNs), one or more recurrent neural networks, or any other suitable neural network configuration. In machine learning, deep convolutional neural networks generally refer to a type of feedforward artificial neural network in which the connectivity pattern among its neurons is inspired by the organization of the animal visual cortex, whose individual neurons are arranged in such a way that they respond to overlapping regions that form the visual field. In contrast, recurrent neural networks (RNNs) generally refer to a class of artificial neural networks where the connections between units form a directed loop. Such connections create an internal state of the network that allows the network to exhibit dynamic temporal behavior.Unlike feedforward neural networks (such as convolutional neural networks), RNNs can use their internal memory to process arbitrary sequences of inputs. As such, RNNs can extract the correlation between the changing tissue environment, lesion development, and the energy delivered by the RF probe in order to better identify and predict changes in the tissue environment and treatment patterns to control the RF energy delivery in response to the changing tissue environment in real time. The system can also be configured to determine an error between the controlled RF power supply and the detected tissue environment. In such modes, the method may further include optimizing the deep learning network based on the error. More specifically, in certain modes, the 112 processors can be configured to optimize a cost function to minimize the error. For example, in one mode, the step of optimizing the cost function to minimize the error may include the use of a stochastic approach, such as a stochastic gradient descent (SGD) algorithm, which iteratively processes portions of the collected data and adjusts one or more parameters of the deep neural network based on the error.As used herein, stochastic gradient descent generally refers to a stochastic approximation of the gradient descent optimization method to minimize an objective function written as a sum of differentiable functions. More specifically, in one configuration, 112 processors can be configured to implement supervised learning to minimize error. As used herein, “supervised learning” generally refers to the machine learning task of inferring a function from labeled training data. Once the deep neural network is trained, the system's 110 controller is configured to manage RF power delivery based on the deep learning network. More specifically, the data collected from the system is used as input to the deep learning network that controls RF power delivery. Example Multiple radiofrequency electrical stimulation assays (500 kHz) were administered to chicken breast (in vitro) maintained at 37°C to compare the lesion sizes created by the adaptive controlled multivariable ablation paradigm of the present invention with conventional temperature-controlled radiofrequency ablation. All assays were administered via a standard ablation probe (PMP-22-100, Avanos Medical, Alpharetta, GA) and a manually controlled generator (Radienles, Burlington, MA) to a piece of raw chicken breast tissue. Three radiofrequency stimulation methods were tested, and three assays were performed for each method. The radiofrequency stimulation methods were as follows: lA / t / ZUZÓ / UtWZ I t (1) Adaptive multivariate stimulation. Radiofrequency stimulation was delivered via the standard temperature-controlled radiofrequency ablation probe for the first 60 seconds, then controlled by tissue impedance thereafter. Specifically, electrical power was increased to reach a set temperature of 80 °C for 60 seconds, and then power was increased again until impedance rose to levels above 1000 Ω. The impedance peak typically occurred a few seconds before the 60-second mark, making the entire test duration approximately 117–119 seconds. (2) Temperature control at 95 °C for 120 seconds (high temperature radiofrequency ablation). (3) Temperature control at 80 °C for 120 seconds (standard radiofrequency ablation). It is known that ablative temperatures above 100 °C cause tissue charring, which significantly limits lesion size. Therefore, the high-temperature group marks the practical limit of lesion size achievable with a temperature-controlled paradigm and our instrumentation. The lesions formed in the tissue by radiofrequency ablation were evaluated as follows: The long (b) and short (a) semi-axes of the lesions were measured in two dimensions. All lesions resembled a prolate spheroid in shape (i.e., the shape of an American football). The volume of each lesion was calculated accordingly as a prolate spheroid: volume = (Q) * nb2a. Table 1 Injury Method Length A (mm) Length B (mm) Injury Volume (mm3) % Volumetric Change Compared to Standard Adaptive Control 6.75 4.00 452.16 278.11 (80 °C for 60s, Z ~60s) 7.00 4.00 468.91 7.00 3.75 412.13 High Temperature (95 °C, 5.25 3.50 269.26 185.67 120s) 6.50 3.25 287.44 6.50 3.50 333.36 Standard (80 °C, 120 s) 5.25 3.00 197.82 5.00 2.00 83.73 5.25 3.00 197.82 lA / t / ZUZÓ / UtWZ I t As shown in Table 1 above, the lesions formed by the adaptive multivariate stimulation of the present invention were on average 278% larger in volume than those produced by standard temperature-controlled ablation (80 °C), and 150% larger than those produced by high-temperature ablation (95 °C) (Table 1). This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to implement the invention, including the manufacture and use of any device or system and the mode of any incorporated method. The patentable scope of the invention is defined by the claims and may include other examples that occur to those skilled in the art. Such other examples are claimed to be within the scope of the claims if they include structural elements that do not differ from the literal language of the claims or if they include equivalent structural elements with insubstantial differences from the literal language of the claims.

Claims

1. A radiofrequency (RF) ablation system for performing an RF ablation procedure, the RF ablation system comprising: a power source for delivering energy to a target site of a patient's body; one or more power delivery devices electrically coupled to the power source; two or more sensors for measuring at least two factors, respectively, related to the RF ablation procedure; and at least one processor configured to perform a plurality of operations, the plurality of operations comprising: (i) measuring the at least two factors related to the RF ablation procedure; (ii) determining a first operating threshold for the power delivery device based, at least in part, on a first factor of the at least two factors;(iii) controlling the energy delivery device based on the first operating threshold to create a lesion at the target site within the patient; (iv) determining a second operating threshold for the energy delivery device; (v) switching control of the energy delivery device from the first factor to the additional factor; and (vi) controlling the energy delivery device based on the second operating threshold to further develop the lesion at the target site within the patient.

2. The system of claim 1, wherein the at least two factors comprise at least two of: power, current, voltage, impedance, tissue temperature at the target site, temperature of a coolant associated with a cooling device for the RF ablation procedure, stimulation duration (time), rate of change of current, rate of change of voltage, rate of change of power, rate of change of tissue temperature at the target site, rate of change of coolant temperature, pressure at the target site, gas formation at the target site, rate of change of gas formation at the target site, or a combination thereof.

3. The system of claim 2, wherein one of the at least two factors is the rate of change of the tissue impedance.

4. The system of any of claims 1-3, wherein the system is configured to continuously monitor and record at least two factors.

5. The system of any of claims 1-4, wherein the first factor is a tissue temperature at the target site.

6. The system of any of claims 1-5, wherein the additional factor is the tissue impedance or the rate of change of tissue impedance at the target site within the patient.

7. The system of any of claims 1-6, wherein the system is configured to determine at least one additional operating threshold for the power supply device based, at least in part, on a third factor; and to switch control of the power supply device from the first operating threshold or the second operating threshold to the third operating threshold to further develop the injury at the target site.

8. The system of any of claims 1-7, wherein at least one of the two or more sensors is configured to measure a respective factor related to the ablation procedure at the target site.

9. The RF ablation system of any of claims 1-8, wherein the one or more power delivery devices comprise an RF probe comprising: an elongated member having a proximal end and a distal end, the distal end comprising an electrically and thermally conductive power delivery device for delivering electrical and RF power to a patient's body, the RF probe having at least one electrode and an electrically and thermally conductive portion having a temperature sensing element; and one or more ablation enhancement features comprising: a cooling device extending within the elongated member, a suction mechanism having a suction path, a fluid injection mechanism having a fluid path, and / or a directional power delivery mechanism.

10. The system of claim 9, wherein the two or more sensors comprise at least one thermocouple positioned in the RF probe.

11. The system of any of claims 1-10, wherein the system is configured to switch the control of the power supply device from the first factor to the additional factor after the first operating threshold is reached.

12. A radiofrequency (RF) probe comprising: an elongated member having a proximal end and a distal end, the distal end comprising an electrically and thermally conductive power delivery device for delivering electrical and radiofrequency power to a target site on a patient's body, the electrically and thermally conductive power delivery device having an electrically and thermally conductive portion having at least one electrode and a temperature sensing element; and at least one ablation enhancement feature configured to enhance lesion formation when the RF probe is applied to a patient's tissue in an ablation procedure.

13. The RF probe of claim 12, wherein at least one electrode is porous.

14. The RF probe of claim 13, wherein the at least one ablation enhancement feature comprises a suction mechanism having a suction path, wherein the suction path is defined by the interior of the elongated member extending from the distal end to the proximal end.

15. The RF probe of claim 13, wherein the at least one ablation enhancement feature comprises a fluid injection mechanism having a fluid path, wherein the fluid path is defined by the interior of the elongated member extending from the distal end to the proximal end.

16. The RF probe of any of claims 12-15, wherein the at least one ablation enhancement feature comprises a suction mechanism having a suction path and / or a fluid injection mechanism having a fluid path.

17. The RF probe of claim 16, further comprising an additional electrode disposed within the suction path and / or the fluid path.

18. The RF probe of claim 16, wherein the suction path comprises a suction channel within the elongated member and the fluid path comprises a fluid channel within the elongated member. lA / t / ZUZÓ / UCW / I t 19. The RF probe of any of claims 12-18, wherein the at least one ablation enhancement feature is defined by the electrode being formed in a geometric shape extending along a portion of the elongated limb such that the electrode is configured to individually target rotational sections of the patient tissue surrounding the elongated limb.

20. The RF probe of any of claims 12-19, wherein the at least one ablation enhancement feature comprises a plurality of secondary electrodes composed of spikes extending from the elongated member that are configured to surround a target patient tissue area in a three-dimensional orientation.

21. The RF probe of any of claims 12-20, wherein the elongated member further comprises one or more internal lumens for containing a coolant therein.

22. A method for performing a radiofrequency (RF) ablation procedure with an RF probe, wherein the method comprises the steps of: measuring at least two factors related to an ablation procedure; determining a first operating threshold for the RF probe based, at least in part, on a first factor; controlling the RF probe based on the first operating threshold to create a lesion at a target site within the patient; determining a second operating threshold for the RF probe based, at least in part, on a second factor; switching control of the RF probe from the first factor to the second factor; and controlling the RF probe based on the second operating threshold to further develop the lesion at the target site within the patient.

23. The method of claim 22, wherein the step of switching the RF probe control from the first factor to the second factor occurs after the first operating threshold is reached.

24. The method of any of claims 22-23, further comprising the steps of: collecting data related to the operation of the RF probe during the measurement, first and second operating thresholds, control, and switching stages; feeding the collected data into a deep learning network configured to learn the measurement, determine the first and second operating thresholds, control, and switch the RF ablation procedure-related steps; and controlling the RF probe based on the deep learning network.

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