Ablation apparatus and system to limit nerve conduction
A surgical system and the associated methods for use in Minimally Invasive Surgical procedures for use in the short- and long-term termination of signals through nerves. Such a procedure is an improvement over the current state-of-the-art because of the use of a tightly coupled single-needle bi-polar probe. The proximity of both electrodes, to the nerve or tissue targeted for the treatment, is such that it reduces the losses experienced with external electrodes (e.g. plates or probes). Further, the probe has features associated with locating the probe and dispensing or sampling far above the probes currently available. The resulting improvements provide a quantum leap in technology for the associated medical industries and a base line for these procedures in the future.
The present invention relates to a method and device used in the field of Minimally Invasive Surgery (or MIS) for interrupting the flow of signals through nerves. These nerves may be rendered incapable of transmitting signals either on a temporarily (hours, days or weeks) or a permanent (months or years) basis. This new device itself consists of a single puncture system, which incorporates both an active and return electrode capable of creating areas of nerve destruction, inhibition and ablation; a generator for precisely delivering RF energy, and the method necessary for properly locating the active tip and generating energy to ablate target nerves.
BACKGROUND OF THE INVENTIONThe human nervous system is used to send and receive signals. The pathway taken by the nerve signals convey sensory information such as pain, heat, cold and touch and command signals which cause movement (e.g. muscle contractions).
Often extraneous, undesired, or abnormal signals are generated (or are transmitted). Examples include (but are not limited to) the pinching of a minor nerve in the back, which causes extreme back pain, or the compression (or otherwise activation) of nerves causing referred pain. Also with certain diseases the lining of the nerves is compromised, or signals are spontaneously generated, which can cause a variety of maladies, from seizures to pain or (in extreme conditions) even death. Abnormal signal activations can cause many other problems including (but not limited to) twitching, tics, seizures, distortions, cramps, disabilities (in addition to pain), other undesirable conditions, or other painful, abnormal, undesirable, socially or physically detrimental afflictions. This device can be used to treat various types of nerve conditions. Such as functional applications to innervations of the posterior neck muscles that will relieve headaches, muscle strain, and pain. The device can be used to treat abnormal muscle activity a result of over stimulation of peripheral nerves, for relief of pain, spasticity, and dystonias. Further, conditions such as hyperhidrosis, rhinorrhea, drooling, and facial flushing, caused by the overactive signals from sympathetic and parasymapathetic nerve path ways, can be treated.
In other situations, the normal conduction of nerve signals can cause undesirable effects. For example in cosmetic applications the activation of the corrugator supercilli muscle causes frown lines which may result in permanent distortion of the brow (or forehead); giving the appearance of premature aging. By interruption of the corrugator supercilli activation nerves, this phenomenon may be terminated. Other cosmetic applications include all neck and facial expression muscles, which are innervated by cranial nerves (including, but not limited to, the orbicularis oculi, orbicularis ori, frontalis, procerus, temporalis, masseter, zygomaticus major, depressor anguli oris, depressor labii inferioris, mentalis, platysma, and/or corrugator supercili muscles). Further, Platysma myoides, Procerus muscles, back muscles, back pain, and other pain/abnormal muscle or nerve activations would be treatable.
This technology describes an improved method of interrupting signal flows through nerve fibers with a new single puncture technique; used in the emerging field of Minimally Invasive Surgery (or MIS). Interrupting such flows is done using electricity to form an electrical circuit with the nerve. The circuit created is formed with a source of energy connected to an active electrode with a return path again connected to the source.
Traditional electrosurgical procedures use either a unipolar or bipolar device connected to that energy source. A unipolar electrode system includes a small surface area electrode, and a return electrode. The return electrode is generally larger in size, and is either resistively or capacitively coupled to the body. Since the same amount of current must flow through each electrode to complete the circuit; the heat generated in the return electrode is dissipated over a larger surface area, and whenever possible, the return electrode is located in areas of high blood flow (such as the biceps, buttocks or other muscular or highly vascularized area) so that heat generated is rapidly carried away, thus preventing a heat rise and consequent burns of the tissue. The advantage of these system is the ability to place the unipolar probe exactly where it is needed and optimally focus the energy where desired. The disadvantage of the system is that the return electrode must be properly placed and in contact throughout the procedure. A resistive return electrode would typically be coated with a conductive paste or jelly. If the contact with the patient is reduced or if the jelly dries out, a high-current density area would result, increasing the probability for burns at the contact point.
Bipolar electrode systems use a two surface device (such as forceps, tweezers, pliers and other grasping type instruments) where two separate surfaces can be brought together mechanically under force. Each opposing surface is connected to one of the two source connections of the electrical generator. Then the desired object is held and compressed between the two surfaces. Then when the electrical energy is applied, it is concentrated (and focused) so that tissue can be cut, desiccated, burned, killed, stunned, closed, destroyed or sealed between the grasping surfaces. Assuming the instrument has been designed and used properly, the resulting current flow will be constrained within the target tissue between the two surfaces. The disadvantage of the conventional bipolar system is that the target tissue must be properly located and isolated between these surfaces. To reduce extraneous current flow the electrodes can not make contact with other tissue, which often requires visual guidance (such as direct visualization, use of a scope, ultrasound or other direct visualization methods) so that the target tissue is properly contained within the bipolar electrodes themselves, prior to application of electrical energy.
In recent years, considerable efforts have been made in refining sources of RF or electrical energy, as well as devices for applying electrical energy to specific targeted tissue. Various applications such as tachyarrhythmia ablation have been developed, whereby accessory (extra) pathways within the heart conduct electrical energy in an abnormal pattern. This abnormal signal flow results in excessive, and potentially lethal cardiac arrhythmias. RF ablation (as it is called) delivers electrical energy in either a bipolar or unipolar configuration utilizing a long catheter, similar to an EP (electrophysiology) catheter. That catheter (consisting of a long system of wires and supporting structures normally introduced via an artery or vein which leads into the heart) is manipulated using various guidance techniques, such as measurement of electrical activity, ultrasonic guidance, and/or X-ray visualization, into the target area. Electrical energy is then applied and the target tissue is destroyed.
A wide variety of technology in the development of related systems, devices and EP products has already been disclosed. For example, U.S. Pat. No. 5,397,339 (issued Mar. 14, 1995) describes a multipolar electrode catheter, which can be used to stimulate, ablate, obtain intercardiac signals, and can expand and enlarge itself inside the heart. Other applications include the ability to destroy plaque formations in the interior of lumens within the body; using RF energy applied near (or at the tip of) catheters such as described in U.S. Pat. No. 5,454,809 (issued Oct. 3, 1995) and U.S. Pat. No. 5,749,914 (issued May 12, 1998). In these applications a more advanced catheter (though similar to the EP catheters (described above)) contains an array of electrodes that is able to selectively apply energy in a specific direction. This device allows ablation and removal of asymmetric deposits/obstructions within lumens in the body. In that application, guidance may also be applied in various forms. U.S. Pat. No. 5,098,431 (issued Mar. 24, 1992), discloses another catheter based system for removing obstructions from within blood vessels. Parins in U.S. Pat. No. 5,078,717 (issued Jan. 7, 1992) discloses yet another catheter to selectively remove stenotic lesions from the interior walls of blood vessels. Auth in U.S. Pat. No. 5,364,393 (issued Nov. 15, 1994) describes a modification of the above technologies whereby a guide wire (a much smaller wire which goes through an angioplasty device and is typically 110 cm or longer) has an electrically energized tip, which creates a path to follow and thus guides itself through the obstructions.
In applications of a similar nature, catheters which carry larger busts of energy (for example from a defibrillator) into chambers of the heart have been disclosed. These catheters are used to destroy both tissues and structures as described in Cunningham (see U.S. Pat. No. 4,896,671 issued Jan. 30, 1990) that describes a catheter for delivery in electroshock ablative therapy.
One application of this technology would induce the elimination of glabellar furrowing by interrupting the conduction of nerve signals to muscles causing frown wrinkles. Traditional treatments have included surgical forehead lifts, resection of corrugator supercilli muscle, as described by Guyuron, Michelow and Thomas in Corrugator supercilli muscle resection through blepharoplasty incision., Plastic Reconstructive Surgery 95 691-696 (1995). Also, surgical division of the corrugator supercilli motor nerves is used and was described by Ellis and Bakala in Anatomy of the motor innervation of the corrugator supercilli muscle: clinical significance and development of a new surgical technique for frowning., J Otolaryngology 27; 222-227 (1998). These techniques described are highly invasive and sometimes temporary as nerves regenerate over time and repeat or alternative procedures are required.
More recently, a less invasive procedure to treat glabellar furrowing involves injection of botulinum toxin (Botox) directly into the muscle. This produces a flaccid paralysis and is best described in The New England Journal of Medicine, 324:1186-1194 (1991). While minimally invasive, this technique is predictably transient; so, it must be re-done every few months.
Specific efforts to use RF energy via a less sophisticated two needle bipolar system has been described in an articleby Hernandez-Zendejas and Guerrero-Santos called Percutaneous Selective Radio-Frequency Neuroablation in Plastic Surgery, Aesthetic Plastic Surgery, 18:41 pp 41-48 (1994) They described a bipolar system using two needle type electrodes. Utley and Goode described a similar system in Radio-frequency Ablation of the Nerve to the Corrugator Muscle for Elimination of Glabellar Furrowing, Archives of Facial Plastic Surgery, Jan-Mar, 99, VI P 46-48. Later they were granted U.S. Pat. No. 6,139,545 (issued Oct. 31, 2000), which fully described the two needle bipolar system. These systems were unable to produce permanent results (i.e. greater than a few months) because of limitations in the energy and their polar configurations and like with Botox, would have required periodic repeat procedures.
There are many ways of properly locating an active electrode near the target tissue and determining if it is in close proximity to the nerve. Traditional methods have included stimulation by using either unipolar and bipolar energy by means of a test pacemaker pulse prior to the implantation of a pacemaker or other stimulation device. A method of threshold analysis called the ‘strength duration curve’ has been used for many years. This curve consists of a vertical axis (or Y-axis) typically voltage, current, charge or other measure of amplitude, and has a horizontal axis (or X-axis) of pulse duration (typically in milliseconds). Such a curve is a rapidly declining line, which decreases exponentially as the pulse width is increased. This curve is described on pp31 ff in The Third Decade of Pacing, by Barold and Mugica (1982) and also on pp 245 in The Biomedical Engineering Handbook” CRC Press, IEEE Press, Ed by J. D. Bronzino, (1995).
Various stimulation devices have been made and patented. The process of stimulation/ablation using a two-needle system is disclosed in U.S. Pat. No. 6,139,545 (Oct. 31, 2000). This process is described in reverse, where the area not desired for detection of ancillary tissue is treated with stimulation then ablation. The process is best described in U.S. Pat. No. 5,782,826 (issued Jul. 21, 1998).
The new method and device of this preferred embodiment also uses (among other potential methods of locating the tip of the electrode in proximity to the target nerve) stimulation, followed by ablation. In this process the energy is delivered via the single puncture MIS system (as later described). This unique technology and resulting device is a single needle that contains both electrodes. It will access the site via a single puncture and will be used with MIS surgical techniques. It will also have features that provide for placement and have substantial added benefits, which are described later in this document.
SUMMARY OF THE INVENTIONThe primary aspect, of the present invention, is to provide a single-needle type puncture entry way for bi-polar electrodes for delivering RF energy near the nerve (to terminate signal flow), in a minimally invasive procedure. Other aspects of this invention will be apparent from the appended claims, descriptions and drawings that follow.
Important aspects of this invention include:
A visible probe tip illumination to aide in positioning;
A hollow lumen for delivery of medication, often, but not limited to, anesthetic;
Delivery of ionizing radiation, via laser, to probe tip for direct energy delivery;
Coordination of ionizing radiation and RF energy delivery;
Unique probe identification;
Prior usage detection to eliminate potential contamination or unauthorized re use;
Procedure power settings matched to probe internal identification;
Direct reading of ablation probe temperature and impedance;
Pre-stored arbitrary amplitude modulation envelopes with multi-frequency for controlled energy delivery;
Controlled metered energy delivery determines permanence;
Multi-frequency operation for optimal power delivery;
Dynamic impedance matching for optimal power delivery;
Integrated dielectric insulator as fiber optic for illumination, thus reducing diameter;
Auxiliary nerve locator probe;
Depth markings on auxiliary probe;
Auxiliary probe needle shaft insulation;
Dual needle tipped auxiliary probe;
Electronic guidance of ablation probe to auxiliary probe;
Electronic guidance measures and displays current proportional probe distances;
Electronic guidance variable frequency audio tone proportional to distance/sense current;
Electronic guidance variable amplitude audio tone proportional to distance/sense current;
Electronic guidance variable frequency/flash rate of ablation tip illumination proportional to distance/sense current;
Illumination of florescent-tagged marker;
Detection of florescent emission of tagged marker;
Simultaneous illumination of florescent-tagged marker and emission detection;
Simultaneous illumination of florescent-tagged marker by means of a tunable laser;
Integrated hollow biopsy electrode for florescent-tagged tumor sampling;
Integrated hollow electrode for medication delivery to tagged tumor;
Integrated hollow electrode for photo-medication delivery to tagged tumor with illumination activation source; and
Another aspect of the invention is a probe usage register to reduce or eliminate chance of patient cross contamination.
This invention is an improved device (and method for its use) that will allow the physician to terminate signal flow through nerves, in a minimally invasive manner, by requiring only a single-needle type puncture. Said method and device would allow for a reduced patient recovery time; the patient would be awake during the procedure; using only a local (or very little) anesthetic; have a substantially reduced risk of infection; less of a risk of intensive care (or hospital stay), and subsequently, a reduced associated costs. Inasmuch, the patient would more rapidly return to a normal lifestyle as compared to many procedures requiring open surgery.
This single-puncture device (hereafter called ‘single-pass’) presents an improvement over conventional uni-polar systems because it does not require a separate return electrode, which is attached to the patient at a remote site and subsequently must be maintained during the surgical procedure. Also, it represents an improvement over bi-polar electrodes and earlier two needle systems, because it concentrates the energy specifically at the desired location (by use of one active electrode) and when ablation areas need to be precisely focused this device may best accomplish that task.
The device (and the methods needed to operate it) can be used to terminate, stop or inhibit (on a temporary, semi-permanent or even permanent basis) the transmission of nerve signals to the muscles, organs and receivers of nerve signals, which convey activation, perception, pain signals or other nervous impulses. In the preferred embodiment, the active electrode (or the probe/needle tip) may be positioned by various guidance and/or sensing means. This includes (but is not limited to) ultrasound, traditional pace/sense (apply stimulating signals and observe placement of the electrode in proximity to the target nerve), manual palpitation, proper anatomical positioning, X-ray, CT, MRI, PET or other radiation or emission type imaging means, fiber-optic video, external location (and marking) and subsequent location by illuminating the probe tip or by other similar means.
In addition to the ‘single-pass’ needle, the complete system shall include an intelligent external energy generator, which can be used either by programmed or manual control. The manual control may be mitigated (or limited for the protection of the patient) by means of various sensors including (but not limited to) impedance (and the change in impedance), temperature (and the change in temperature), normal voltage (or current) regulation, etc. Said generator will generate RF energy in the frequency range of 50 Khz to 2.5 Mhz, in a controlled manner.
The generator will also be usable under program control. Said programming will deliver a predetermined “bolus” (or packet) of electrical energy, whereby the dose is adjustable (within limits) by the physician proportional to the desired effect. This bolus will be predetermined in clinical studies and may have preset parameters such as minimal effect, average effect, maximum effect, corresponding to a low, normal and high-output level. The output cycle will be activated by the physician via footswitch, a button on the probe itself, voice or other similar method of activation methods. When the bolus output is activated it may be terminated (at any time) by releasing activation means (i.e. the footswitch, button or the like). However, it will provide output no greater or longer than the activation device is held down, and will also be limited to the length of time and dosage preset. To deliver a second packet of energy, the activation mechanism must be released for (an internally set) time period before another packet of energy may be delivered. Also, because this technology may be used in various applications (e.g. plastic surgery, spinal nerves causing back pain, and other applications where terminating signal flows through nerves is desired) the delivery systems (i.e. single-pass needle or probe, and the generator required to power same) may be of differing sizes, surface areas or mechanical configurations. Some may even require a substantially different amount or type of energy packet. Program setting and preferences made be controlled for the different applications by providing a specific hand tool device that would then contain a coded circuit, connector or other means of providing identification to the generator so that it may deliver the required energy packets automatically for the different applications or methods.
The methods of ablation may include both a linear or circular zone. The effective ablation area may be modified by “laying down” a series of individual ablation zones, thus creating a line of ablated tissues. This would be possible by withdrawing, inserting, and/or moving the active tip while ablating in the successive zones, which would expanding the liner component of any lesion produced. In the alternative, the effective zone of ablation could be extended circumferentially by manipulating the tip during the ablation cycle in small circles, thereby mechanically moving the tip enlarging the effective zone of ablation.
BRIEF DESCRIPTION OF THE DRAWINGS
Defined below are the terms used here within:
Medical Terms
- Corrugator supercili muscles—skeletal muscles of the forehead that produce brow depression and frowning
- Cepressor anguli oris—skeletal muscle of the corner of the mouth that produces depression of the corner of the mouth
- Depressor labii inferioris—skeletal muscle of the lower lip that causes the lip to evert and depress downward
- Dystonias—medical condition describing an aberrant contraction of a skeletal muscle which is involuntary
- Frontalis—skeletal muscle of the forehead that produces brow elevation or raising of the eyebrows
- Hyperhidrosis—condition of excessive sweat production
- Masseter—skeletal muscle of the jaw that produces jaw closure and clenching
- Mentalis—skeletal muscle of the lower lip and chin which stabilizes lower lip position a
- Orbicularis oculio—skeletal muscle of the eyelid area responsible for eyelid closure
- Orbicularis ori—skeletal muscle of the mouth area responsible for closure and competency of the lips and mouth
- Parasymapathetic—refers to one division of the autonomic nervous system
- Platysma myoides—skeletal muscle of the neck that protects deeper structures of the neck
- Platysma—same as above
- Procerus muscles—skeletal muscle of the central forehead responsible for frowning and producing horizontal creasing along the nasofrontal area
- Procerus—same as above
- Rhinorrhea—excessive nasal mucous secretions
- Supercilli—a portion of the corrugator muscle that sits above the eyelids
- Temporalis—skeletal muscle of the jaw that stabilized the temporamandibular joint
- Zygomaticus major—skeletal muscle of the face that produces smiling or creasing of the midface
Electrical Terms - ADC: Analog to digital converter
- ASCII: American standard of computer information interchange.
- BAUD: Serial communication data rate in bits per second.
- BYTE: Digital data 8-bits in length
- CHARACTER: Symbol from the ASCII set.
- CHECKSUM: Numerical sum of the data in a list.
- CPU: Central processing unit.
- EEPROM: Electronically erasable programmable read only memory.
- FLASH MEMORY: Electrically alterable read only memory. (See EEPROM)
- GUI: Graphical user interface.
- HEXADECIMAL: Base 16 representation of integer numbers.
- 12C BUS: Inter Integrated Circuit bus. Simple two-wire bi-directional serial bus developed by Philips for an independent communications path between embedded ICs on printed circuit boards and subsystems.
The I2C bus is used on and between system boards for internal system management and diagnostic functions.
- INTERRUPT: Signal the computer to perform another task
- PC: Personal computer.
- PWM: Pulse-width modulation
- ROM: Read only memory.
- WORD: Digital data 16-bits in length
This section provides information on the overall operation of this system.
In normal operation, the novel probe 371 would combine a unique bipolar configuration in a single MIS needle, is inserted into the patient using MIS techniques. The probe, which may contain and/or convey various functions described later, is initially guided anatomically to the region of the anticipated or desired location. Various means of locating the tip 301 are utilized of placing the zone of ablation in the proper area to interrupt signal flows through the nerve 101.
DETAILED DESCRIPTION OF DEVICE OPERATIONThis section refers to the drawings to describe use of the probe. There are many combinations of electrode diameters and tip shapes are possible. The ‘novel’ probe performs a variety of functions, such as stimulation, optical and electronic guidance, medication delivery, sample extraction, and controlled ablation. This bi-polar electrode is designed as a small diameter needle inserted from a single point of entry thus minimizing scaring and simplifying precise electrode placement. This low cost, compact design provides a new tool to the art.
Probes may emit fiber optic illumination for deep applications using electronic guidance as taught in
Stimulation/Ablation
First the probe electrode 301 must be in the desired location relative to the target nerve 101 (
For example, both a high amplitude sine wave 910 (
The output of the modulator 415 is applied to the input of the power amplifier 416 section. The power amplifier's 416 outputs are then feed into the impedance matching network 418, which provides dynamic controlled output to the biologic loads that are highly variable and non-linear, and require dynamic control of both power levels and impedance matching. The tuning of the matching network 418 is performed for optimal power transfer for the probe, power level, and treatment frequencies settled. The system's peak power is 500 watts for this disclosed embodiment. Precise control is established by the proximity of the tip and the control loops included in the generator itself The final energy envelope 420 is delivered to probe tip 301 and return electrodes 302.
This precise control of energy permits extension of the ablation region(s), 140 and 1203 (
A low energy nerve stimulator 771 has been integrated into the system to assist in more precise identification of nearby structures and for highly accurate target location. Lastly, additional sensors, such as temperature 311, voltage, frequency, current and the like are read directly from the device and/or across the communications media 403 to the probe.
Directed Ablation
In addition to the substantial radially-symmetric ablation patterns with probes as taught in 371 (
Power Feedback
The power amplifier output430 and buffered the feedback signals 437 are connected to an Analog to Digital converter (or ADC) 431 for processor analysis and control. Said signals 437 control power modulation 420 settings and impact the impedance matching control signals 419. This integrated power signal 437 is recorded to the operating-condition database (
Probe Identification
At power startup, the controller 401(
The controller 401 also verifies selected procedure 1415 (
Nerve Target Location Tools
Prior to treatment, the practitioner may use auxiliary probe 771(
Location Via Florescence Marker Dye
In other procedures, whereby somewhat larger targets are sought, such as more diffuse nerve structures or small areas of abnormal growth (e.g. such as cancer) the injection of specially designed dyes that attach to target structures are used, as taught in
Electronic Probe Guidance
Low energy nerve stimulation current 810 (
Optical Probe Guidance
Disclosed invention provides optical sources 408 that aid in probe placement (
Data and Voice
Real-time engineering parameters are measured such as average power 437, luminous intensity 478, probe current 811, energy 438 and, temperature 330 to be recoded into USB memory 438. Simultaneously, the internal parameters disclosed such as frequency 423, modulation 420 and such are recoded into USB memory 438 as well. Additionally probe, patient, and procedure parameters (
Data Transfer
At procedure conclusion, the system transfers the data 438 recorded to the USB removable memory 1338 and to a file server(s) 1309 and 1307. In the disclosed embodiment, data transfer is performed over Ethernet connection 480. Probe usage records 1460(
Before explaining the disclosed embodiment of the present invention in detail, it is to be understood that the invention is not limited in its application or to the details of the particular arrangement shown. The invention is capable of other embodiments. Further, the terminology used herein is for the purpose of describing the probe and its operation. Each apparatus embodiment described herein has numerous equivalents.
Bi-polar probe 310 represents probes 371, 372, 373 shown in FIGS. 3A-C with exception to type of needlepoint on the probe.
Hollow Electrode 301 often used as a syringe to deliver medication such as local anesthetic. Tip electrode 301 is connected to power amplifier 416 via impedance matching network 418 (
Ablation regions 306 and 140 extend radially about electrode 301 generally following electric field lines. For procedures very close to skin 330 a chance of burning exists in region 306. To minimize the chance of burning, a split return electrode probe 374 in
The bi-polar probe 380 (not drawn to scale) consists of an insulating dielectric body 309 made from a suitable biologically inert material, such as Teflon PTFE or other electrical insulation, that covers split return electrodes 302 and 303. The disclosed conductive return electrodes 302 and 303 are fabricated from medical grade stainless steel, titanium or other electrically conductive material. Hollow or solid split conductive tip electrodes 301 and 311 protrude from the surrounding dielectric insulator 305. The operation of the hollow/split conductive tip is very similar to probe tip 310 as taught in
Bi-polar probe 371 discloses conical shaped electrode 301 and tip 351 for minimally invasive single point entry. Probe diameter 358 is similar to a 20-gage or other small gauge syringe needle, but may be larger or smaller depending on the application, surface area required and depth of penetration necessary. In disclosed embodiment, electrode shaft 302 is 30 mm long with approximately 5 mm not insulated. Lengths and surface areas of both may be modified to meet various applications such as in cosmetic surgery or in elimination of back pain. The conductive return electrode 302 is fabricated from medical grade stainless steel, titanium or other conductive material. The dielectric insulator 305 in the disclosed embodiment is a transparent medical grade material such as polycarbonate, which may double as a light pipe or fiber optic cable. The high intensity light source 408 LED/laser (
The hollow chisel electrode 352 is often used as a syringe to deliver medication such as local anesthetic, medications,/tracer dye. The hollow electrode may also extract a sample. Dielectric insulator 305 in the disclosed embodiment is a transparent medical grade polycarbonate and performs as a light pipe or fiber optic cable. The novel dual-purpose dielectric reduces probe diameter and manufacturing costs. Light source 408, typically a LED or laser (
The bi-polar probe 373 discloses a tapered conical shaped probe for minimally invasive single point entry. It is constructed similarly to probe 371 as taught in
Description of this probe is described in both drawings 2A and 3D. Bi-polar probe 374 (not drawn to scale) consists of insulating dielectric body 309 made from a suitable biologically inert material, such as Teflon, that covers split return electrodes 302 and 303. Conductive return electrodes 302 are fabricated from medical grade stainless steel, titanium or other suitable conductive material. Hollow or solid split conductive tip electrodes 301 and 311 protrude from surrounding dielectric insulator 305. Their operation is very similar to probe tip 380 as taught in
Probe handle (not drawn to scale) encloses memory module 331, on/off switch 310 and mode switch 367. Temperature sensor 330 (located close to tip) monitors tissue temperature. Split electrode 380 (
Connections consist of a tapered dielectric sleeve 309 covering the ridged stainless electrode tube 302. Insulating sleeve 309 is made from a suitable biologically inert material, which covers electrode 302. Dielectric 305 insulates conical tipped electrodes 351 and 301.
See section Detailed Description of Device Operation.
Ablation probe 371 is inserted and directed anatomically into the area where the target nerve to be ablated (Box 531) is located. Test current 811 is applied (Box 532). If probe is located in the immediate proximity of the target nerve a physiological reaction will be detected/observed (Example: During elimination of glabellar furrowing, muscle stimulation of the forehead will be observed). If reaction is observed, then a mark may optionally be applied on the surface of the skin to locate the area of the nerve. Power is applied (Box 535) in an attempt to ablate the nerve. If physiological reaction is not observed, (Box 534) the probe will be relocated closer to the target nerve and the stimulation test will be repeated (Box 536 & 537). If no physiological reaction is observed, the procedure may be terminated (Box 544). Also, the probe may be moved in any direction, up, down, near, far, circular, in a pattern, etc. to create a larger area of ablation for a more permanent result.
In Box 537, if stimulation is observed again, then the ablation power may be set higher (Box 538), alternatively, as mentioned, the needle may be moved in various directions, or a larger dosage of energy may be reapplied, to form a larger area of ablation for more effective or permanent termination of signal conduction through the nerve. After delivery of power (Box 540), stimulation energy may be applied again (Box 541). If there is no stimulation, the procedure is completed (Box 544). If there is still signal flow through the nerve (stimulation or physiological reaction) then the probe may be relocated (Box 542) and the procedure is started over again (Box 533).
Auxiliary probes 771 and 772 (
Operation 530 (
Between each ablation, procedure 540 (
As an example and not a limitation, five ablation regions (140, 141, 142, 143, and 144) are shown in
Probe insertion and placement is same as taught in
In special cases were target nerve 101 or ablation region 640 is in close proximity to second nerve 111 or skin 330 bi-polar probes 371 or 372 (
Probe construction is similar to
This probe may be used in conjunction with any of the therapeutic probes 371 and their derivatives. The needle itself will be very fine in nature, such as an acupuncture type needle. By its small size, numerous needle insertions may be accomplished with no scarring and minimal pain. The probe 771 will be inserted in the vicinity of the target tissue through skin 330. The exposed tip of 771, 702 will be exposed and electrically connected to generator 732 via wire 734. The surface of probe 771 is covered with dielectric 704 so the only exposed electrical contact is surface 702 and return electrode 736. Exposed tip 702 will be advanced to the vicinity of target 101 and test stimulation current will be applied. Appropriate physiological reaction will be observed and when the tip 702 is properly located, depth will be noted via observing marks 765. External mark 755 may be applied for reference. Ablation probe 371 may then be advanced to the proximity of the target tissue under the X mark 755 and ablation/nerve destruction as described elsewhere may be performed.
Dual tipped probe 772 offers an additional embodiment that eliminates return electrode pad 736. Probe frame/handle 739 holds two fine needles, 702 and 701, in the disclosed embodiment that are spaced a short distance (a few mm)-mm apart (730). The shaft of conductive needle 701 is covered with dielectric insulator 706, similar to the construction of probe 771 (
Probes 702 and 701 are very small gage needles similar in size to common acupuncture needles, thus permitting repeated probing with minimal discomfort, bleeding, and insertion force. Sharp probes are inserted thru skin 330 and muscle layer(s) 710 near nerve 101. The practitioner locates target nerve 101, then the skin surface may be marked 755 as location aide for ablation step as shown in flow chart (
Auxiliary probes 771 and 772 (
Auxiliary probe 771 and 772 provide a method to quickly locate shallow or deep target structures. Shallow structures are typically marked with ink pen allowing illuminated ablation probe 371 or its equivalents to be quickly guided to mark 755. Optionally, non-illuminated probes may be used by the practitioner who simply feels for the probe tip. For deep structures, probe 771 may also be employed as an electronic beacon; small current 811 (which will be lower intensity and different from the stimulating current) from probe tip 702 is used to guide ablation probe 372. Amplifier 430 (
Lower energy pulse width modulated (or PWM) sinusoid 920 for coagulation is also well known to electro-surgery art. Variations of cut followed by coagulation are also well known.
Auxiliary probes 771 and 772 (
Ablation probe 372 is inserted thru skin 330 and muscle layer(s) 710 near nerve 101. Illumination source 408 permits practitioner to quickly and accuracy guide illuminated 448 ablation probe 372 into position. Illumination 448 from ablation probe as seen by practitioner 775 is used as an additional aide in depth estimation. Selectable nerve simulation current 811 aids nerve 101 location within region 1204. This novel probe placement system gives practitioner confidence system is working correctly so s/he can concentrate on the delicate procedure. Accurate probe location permits use of minimal energy during ablation, minimizing damage to non-target structures and reducing healing time and patient discomfort.
Region 1203 shows the general shape of the ablation region for conical tip 301. Tip 301 is positioned in close proximity to target nerve 101. Ablation generally requires one or a series of localized ablations. Number and ablation intensity/energy are set by the particular procedure and the desired permanence.
Five ablation regions are illustrated 140, 141, 142, 143, and 144; however, there could be more or less regions. Ablation starts with area 144, then the probe is moved to 143 and so on to 140, conversely, ablations could start at 140 and progress to 144. Also, the practitioner could perform rotating motions, thus further increasing the areas of ablation and permanence of the procedure. Between each ablation procedure 540 (
Controller 101 maintains local probe 1460, patient 1430, and procedure 1410 databases. All work together to insure correct probes and settings are used for the desired procedure. Automatically verifying that the attached probe matches selected procedure and verifying probe authentication and usage to avoid patient cross contamination or use of unauthorized probes. Automatic probe inventory control quickly and accurately transfers procedure results to the billing system.
From a touch screen, the practitioner selects the desired procedure from list 1410. For example “TEMPORARY NERVE CONDUCTION” 1411, “SMALL TUMOR 1CC” 1412, and “SMALL NERVE ABLATE” 1413 are a few of the choices. Each procedure has a unique procedure code 1416 to be used in the billing system. Power range parameter 1417 is a recommended power setting via power level control 404. The recommended probe(s) Associated with procedure 1415 and power range parameter 1417 are listed in parameters 1419. With the probe connected, the part number is read from memory 331 (
From touch screen 450 (
During the procedure (
Use of a USB memory stick permits continued operation in the event of a network 1326 failure Data is loaded to memory 1338 for simple transfer to office computer 1306 (
If computer network 1326 such as Ethernet 802.11 or wireless 802.11x is available, files are mirrored to local storage 1309, remote server 1307. The remote server (typically maintained by equipment manufacture) can be remotely update procedure(s). To insure data integrity and system reliability a high availability database engine made by Birdstep of Americas Birdstep technology, Inc 2101 Fourth Ave. Suite 2000, Seattle Wash. is offered as an example. The Birdstep database supports distributed backups, extensive fault and error recovery while requiring minimal system resources.
From a touch screen, the practitioner selects or enters patient name from previous procedure 1430 and creates a new record 1433. Similarly, a procedure is selected from 1410 (for example “TEMPORARY NERVE CONDUCTION” 1411, “SMALL TUMOR 1CC” 1412, and “SMALL NERVE ABLATE” 1413). Each procedure has a unique procedure code 1416 that is used for the billing system. Other information such as practitioners name 1440, date 1435 is entered to record 1433. As taught above probe appropriate for the procedure is connected and verified, part 1470 and serial number 1469 recorded.
The practitioner enters additional text notes to file 1442 or records them with microphone 455 (
At the end of procedure, records are updated and stored to memory 438. Backup copies are written to USB 1320 memory stick 1338 (
Claims
1) A System for Minimally Invasive Surgery comprising:
- a. an electrically isolated RF Energy Generator, that delivers up to 500 watts of RF energy in amplitude or frequency modulated form with a frequency between 50 Khz and 2.5 Mhz;
- b. a single-needle bi- or multi-polar probe that requires but a single puncture entranceway and has electrodes in close proximity to the extent necessary to promote precision within the procedure itself; and
- c. a secondary means to locate and position said single-needle probe by illumination, the creation of electrical signal or signals, or by use of florescent dye.
2) A generator as described in claim #1 that delivers RF energy regulate-able intelligently by use of dynamic load detection measuring the effective load-by voltage, current, phase or varying frequency comprising:
- a. connection to the probe;
- b. connection to the probe's internal microcontroller for memory and sensor reading and writing if any, and to retrieve procedural, control sequence and limitations that are in turn used for that probe's specific procedure;
- c. display and sound as required for surgical functionality;
- d. memory storage for record keeping of procedural information related to the operating parameters, date, time, sensor measurements taken, and voice or data recording; and
- e. connection to a communication channel such as RS-232, RS485, Ethernet, Bluetooth, or any other viable communication media.
3) A single needle two electrode probe used in a bi- or multi-polar configuration for Minimally Invasive Surgery comprising:
- a. an inner diameter electrode made of surgical grade metal of a size and shape dictated by the application requirement;
- b. a voltage insulator that covers and creates an electrical isolation between the two exposed electrodes; and
- c. an Outer-sleeve return-electrode made of a surgical grade metal with surface area greater than that necessary to eliminate burning of the tissue in contact;
4) A single needle multiple electrode probe used in a multi-polar configuration for Minimally Invasive Surgery comprising:
- a. an inner diameter electrode made of surgical grade metal of a size and shape dictated by the application requirement;
- b. a voltage insulator that covers and creates an electrical isolation between the two exposed electrodes; and
- c. an Outer-sleeve return-electrode made of a surgical grade metal with surface area greater than that necessary to eliminate burning of the tissue in contact;
5) A single needle probe as in claim #3 or #4 with a inner diameter electrode hollow such that injections of medications, florescent dyes and the like can be made and samples of the surrounding tissue can be taken.
6) A single needle probe as in claims #3, #4, or #5 that communicates, to the generator, information related to the procedure, measurements of sensors embedded within the probe and probe specific information.
7) A single needle probe as in claim #3, #4, #5 or #6 with an electrical isolator that is capable of illuminating the area so that placement of the probe can be facilitated;
8) A method for ablating tissues or terminating the flow of nerve impulses utilizing a single puncture probe introduced via a Minimally Invasive surgical techniques comprising:
- a. locating probe tip in close proximity to said nerve or target tissue with a needle type probe having an exposed active area or areas on or near the distal tip, said probe and system to generate RF energy so as to ablate, destroy tissue or render nerve conduction through said nerves impossible on either semi permanent or permanent basis;
- b. placing said probe tip in position so that ablative energy may be selectively delivered to target tissue thus avoiding destruction or areas and tissues that must remain intact and not be destroyed or traumatized; and
- c. delivering RF energy from a tuned RF source so as to destroy target tissues in close proximity to electrode(s) at tip.
9) A method as in claim #7 wherein guidance between auxiliary probes and ablation probes is provided via current signals, illumination or other means.
10) A method as in claim #7 wherein positioning involves placing tip of the probe in desired general area using physiologic and anatomic landmarks with manual guidance.
11) A method as in claim #7 wherein precise positioning is done using illumination from tip region of probe so operator can see exact location of tip through the skin and other intervening structures.
12) A method as in claim #7 whereby the therapeutic probe is guided in to general area desired and then directed precisely under surface marking by observing the location of illumination point emanating from tip of probe.
13) A method as in claim #7 wherein auxiliary probes are inserted into vicinity of target tissues, stimulation energy is applied from the auxiliary probes, location is determined, and the target area is identified by marking the tissue or other means.
14) A method as in claim #7 wherein nerve, muscle, or physiologic reaction is observed by applying stimulation currents from ablative tip(s), thus confirming proper location of tip in relation to target tissue(s).
Type: Application
Filed: Jun 17, 2004
Publication Date: Dec 22, 2005
Inventors: William Janssen (Elizabeth, CO), James Newman (Mountain View, CA), James Jones (Emerald Hills, CA), Jeffrey Buske (Boulder, CO)
Application Number: 10/870,202