WO2007107762A1 - Chauffage indirect - Google Patents
Chauffage indirect Download PDFInfo
- Publication number
- WO2007107762A1 WO2007107762A1 PCT/GB2007/001020 GB2007001020W WO2007107762A1 WO 2007107762 A1 WO2007107762 A1 WO 2007107762A1 GB 2007001020 W GB2007001020 W GB 2007001020W WO 2007107762 A1 WO2007107762 A1 WO 2007107762A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- heating
- target system
- coil
- coil element
- electrically conductive
- Prior art date
Links
Classifications
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
- H05B6/00—Heating by electric, magnetic or electromagnetic fields
- H05B6/02—Induction heating
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
- A61K41/00—Medicinal preparations obtained by treating materials with wave energy or particle radiation ; Therapies using these preparations
- A61K41/0052—Thermotherapy; Hyperthermia; Magnetic induction; Induction heating therapy
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
- H05B6/00—Heating by electric, magnetic or electromagnetic fields
- H05B6/02—Induction heating
- H05B6/04—Sources of current
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
- H05B6/00—Heating by electric, magnetic or electromagnetic fields
- H05B6/02—Induction heating
- H05B6/10—Induction heating apparatus, other than furnaces, for specific applications
- H05B6/101—Induction heating apparatus, other than furnaces, for specific applications for local heating of metal pieces
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
- H05B6/00—Heating by electric, magnetic or electromagnetic fields
- H05B6/02—Induction heating
- H05B6/10—Induction heating apparatus, other than furnaces, for specific applications
- H05B6/105—Induction heating apparatus, other than furnaces, for specific applications using a susceptor
Definitions
- the present invention relates to a method and apparatus for indirectly heating a target system.
- the present invention relates to an apparatus and method in which one or more coils located close to a target system can be energised in a selectable manner to thereby indirectly heat the target system.
- induction heating is a non-contact method that uses high frequency electricity to provide fast, consistent heat to electrically conducting materials. Since the process is non-contact, there is no contamination of the material being heated. It is also very efficient since the heat is actually generated inside the instrument. This can be contrasted with other heating methods where heat is generated in a flame or heating element, which is then applied to the instrument.
- induction heaters where an electrically conductive material needs to be heated in a clean, efficient and controlled manner.
- a disadvantage of induction heating is that it is only applicable to metallic objects.
- indirect heating in which a target system is made up of particles with single magnetic domains and heat is derived from the energy associated with rapid switching of the particles magnetisation vector.
- Another type of indirect heating is hysteresis heating which occurs when a system comprises particles with one or more magnetic domains. Heat is derived from the energy associated with domain wall movement driven by an alternating magnetic field close to the target system.
- hyperthermia is a technique known for destroying cancer cells by raising the temperature of the cancer in the order of 5 0 C or above.
- the subject has been extensively researched over the past 20 years and numerous heating devices have been produced.
- Some hyperthermia devices are available commercially and are based on either focused ultrasound or electromagnetic radiation. However, none of these devices have been able to accurately deliver high heat loads to deeply situated cancers without also destroying the surrounding normal tissues.
- Thermoablation is another technique which can be used to treat cancer cells. During thermoablation burning of the cells occurs by raising the temperature of the cells via heating.
- Microwave Heat produced by microwaves can be directed at tumours that are 1- 3 cm from the surface of the skin. Microwaves are rapidly absorbed as they penetrate deeper into the body. Thus, tumours located at depths greater than 3 cm from the surface of the body cannot be effectively heated with presently used microwave techniques.
- Interstitial RF Interstitial treatments send RF energy through small needles placed into the tumour. After heating, interstitial radioactive therapy material can be introduced into the tumour site through the same probes used to introduce heat (This is called brachytherapy and has been used as a cancer treatment for many years.) Interstitial hyperthermia can also be used with external beam radiation. This technique allows greater control of heat application, but is an, invasive procedure (the placement of needles can be painful and restricts the movement of the patient).
- Ultrasound This technique uses ultra-high frequency sound waves to produce heat within the tumour. Ultrasound is more easily focused than other energy modalities and can be applied to tumours located from the skin to 8 cm within the body. This allows the treatment of tumours unreachable by other external modalities. Ultrasound doesn't require the use of radiowave shielding devices to protect medical personnel during treatment.
- an apparatus for heating a target system comprising: at least one coil element locatable proximate to the target system; at least one capacitor element connected to said coil element; a direct current (DC) power supply connectable to said coil element via a switching element; and a switch controller for selectively switching said switching element on at a desired frequency to thereby heat said target system via indirect heating.
- DC direct current
- a method for heating a target system comprising: locating at least one coil element proximate to the target system, at least one capacitor element being connected in parallel with said coil element; and selectively supplying power to said coil element by selectively connecting a direct current (DC) power supply to the coil element at a desired frequency.
- DC direct current
- a method for destroying cancer cells comprising the steps of: indirectly heating a target system proximate to at least one cancer cell by the steps of: locating at least one coil element proximate to the target system, at least one capacitor element being connected in parallel with said coil element; and selectively supplying power to said coil element by selectively connecting a direct current (DC) power supply to the coil element at a desired frequency.
- DC direct current
- Embodiments of the present invention provide an instrument for the indirect heating of magnetic or magnetisable particles or solids by an alternating magnetic field in the radio range of frequency (about 2kHz to 3MHz).
- the power, frequency and duration of the heating effects can be varied to suit the system to be heated.
- the system is defined as the magnetic or magnetisable particles or solids or electrically conductive or electrically conductible particles or solids plus any other substances such as water, biological tissue or solids in contact with them.
- the instrument can thus be used to heat magnetic or magnetisable particles or solids to test their inherent ability to be heated or to indirectly heat substances in direct contact with the magnetic or magnetisable particles or solids.
- the instrument can also be used to heat electrically conductive particles or solids to test their inherent ability to be heated or to indirectly heat substances in direct contact with the electrically conductive particles or solids.
- Embodiments of the present invention provide an instrument which provides flexibility for a number of operational parameters.
- the frequency of an alternating magnetic field can be varied simply by replacing banks of capacitors.
- the waveform of the alternating magnetic field can be varied to provide, for example, a square wave, sinusoid or saw tooth.
- This has a number of advantages, as will be appreciated by those skilled in the art.
- the size, shape and material of the inductor coil which the target system to be heated is placed in or is placed next to, can be varied. This provides a very versatile system.
- impedance matching does not need to be carried out with a specific coil to be used.
- Embodiments of the present invention provide the advantage that the power output of an indirect heating apparatus can be varied but that this power output which is responsive to an alternating magnetic field strength can be held relatively constant over a particular frequency range.
- Figure 1 illustrates a heating coil and circuitry for energising the coil
- Figure 2 illustrates use of the coil to test heating in a test sample
- Figure 3 illustrates use of a coil to destroy cancer cells.
- Figure 1 illustrates an indirect heating system 10 which includes a winding 11.
- the geometric design of the coil 11 (number of turns, radius and length) has an effect on a magnetic field strength generated by the coil.
- the coil is formed from coiled tubing formed of a metal, such as copper.
- the tubing enables a cooling fluid, such as water, to be pumped through the coil to reduce direct heating effects.
- embodiments of the present invention are not restricted to use of a tubular coil structure nor to a coil structure including any cooling elements.
- a node 12 at an end of the coil 11 is connected to a high voltage rail 13 of a high voltage direct current (DC) power supply 14.
- the low voltage rail 14 is grounded and is connectable to a coil tap 16 via a MOSFET 17.
- the MOSFET 17 provides a current path between its drain and source and this current path can be controlled by selectively providing a control voltage to the gate of the MOSFET.
- This control voltage V CTRL is provided by a function generator 18 which is connected to the gate via a first low resistance element R 1 and higher resistance element R 2 .
- the resistor R-i has a value of 50 ohms whilst the resistor R 2 has a value of 1000 ohms.
- a capacitor bank 19 is connected in parallel with the coil 11 between node 12 and a further end of the coil 11.
- the capacitor element 19 is a removable array of silvered mica tuning capacitors.
- a set of such capacitor elements is provided so that an array of the capacitors can be selected from the set which has a value which can be used to select when resonance occurs in the coil 11. It will be understood that rather than using an array of capacitors single capacitors having various capacitances could be used or indeed a variable capacitor.
- the coil 11 and capacitors 19 form a resonant circuit due to the inductive nature of the coil and the capacitive nature of the capacitors being connected in parallel. When supplied with current at a correct selected frequency the circuit resonates.
- the resonant frequency of the circuit is set by the values of the coil inductance and the capacitors.
- the frequency can be changed by changing the coil or the capacitors or both.
- Using banks of capacitors means that a bank can readily be exchanged for another bank to change the resonant frequency.
- AC alternating current
- the power output of the power supply is adjusted to compensate.
- the waveform of the AC magnetic field can also be adjusted using the control of the function generator 18. This provides an additional level of control but is not required when this level of control is not required.
- the first capacitive element C1 is a 1 ⁇ F 100V polyester capacitor.
- the second capacitive element C2 is a 10 ⁇ F 100V electrolytic capacitor. These are included to help keep the power supply impedance low at radio frequencies. It will be appreciated by those skilled in the art that these capacitors may be replaced by other types or indeed omitted entirely.
- Embodiments of the present invention make use of a direct current (DC) power source. Rather than use an alternating current (AC) power source which would require complex impedance matching in the circuitry, use of a DC power supply overcomes such problems.
- DC direct current
- AC alternating current
- the coil 11 provides an inductor element connected to the bank of capacitors 19.
- the resultant oscillating circuit sometimes referred to as a tank circuit, stores energy in the form of oscillating voltage and current. In this way the capacitor and inductor will exchange energy between them back and forth creating their own AC voltage and current cycles. In this way current through the coil 11 is alternating with the
- FIG 2 illustrates how an embodiment of the present invention can be used to test whether a target system 20 can be heated via indirect heating.
- the coil 11 is provided with power via the circuitry illustrated in Figure 1 and is located close to a target system.
- the target system is defined as the magnetic or magnetisable particle or particles or solids or electrically conductive or electrically conductable particle or particles or solids plus any other substance such as water, biological tissue or solid in contact with them.
- Such material can be introduced into an environment proximate to a location where heating is to be achieved.
- the proximate location may be achieved either by locating the sample within a solenoid type coil or surface coil configurations may be utilised where the sample need not be placed in the coil but only adjacent to it. If a target system is selected which can be readily heated then this heating can be advantageously utilised. By locating the coil 11 close to the target system and then energising the coil indirect heating of the target 20 can be achieved by one or more of the methods noted above. It is to be noted that the samples may be of magnetic non- metallic metal oxide compounds which do not heat by all the same mechanisms as nonmagnetic metals but do use the same AC magnetic field for heating.
- Non-magnetic metals are heated via induction by eddy currents induced by an AC magnetic field which gives rise to dual-resistance heating. If the metals are also magnetic then additional heating via magnetic hysteresis heating is also involved. Plastics may also be heated if they are doped with a necessary magnetic or metallic compound.
- the type of heating induced by an AC magnetic field is hysteresis, Neel and Brownian motion heating. One, two or more of these mechanisms may be in operation in a target sample 20. Whether or not a target sample is heated by the coil 11 or to what degree is measured by a temperature sensor 21 located close to the test sample.
- Figure 3 illustrates how embodiments of the present invention may be used to help destroy cancer cells in a human body.
- a patient 30 with a cancerous cell 31 is identified and the location of the cancerous cell determined.
- Next target systems which can be heated in an indirect manner as noted above are introduced into the patient. These may be injected into a patient and include known techniques for locating themselves proximate to a cancer cell. Alternatively the target system to be heated may be surgically implanted. It is to be understood that according to embodiments of the present invention particles to be heated, and/or cells and formulations etc containing or having particles attached to them, can locate at the target site (e.g. tumor) by passive techniques (random or characteristic properties of the target), direct location to the target site (e.g.
- the coil 11 is then brought into close proximity with the cell 31 and power supplied so as to heat the target system. Heating the target system which is located close to the cancer cell heats the cancer cell. Sufficient heat is provided so as to harm or destroy the cancerous cell.
- the heating properties of the target system are dependent upon many factors including particle size and shape, chemical composition and location. For example, whether the particles are free in solution or attached/ embedded in a solid.
- the rate of heating is dependent upon the AC magnetic field strength and the frequency of the AC magnetic field. For this reason, it is important to be able to change the frequency of the instrument in order to fine the most appropriate frequency for heating the sample.
- the alternating magnetic field strength is adjusted by selecting the power input from the DC power supply.
- the product of the AC magnetic field strength and the frequency of the alternating magnetic field should be less than 4.85 x 10 8 AIvT 1 S '1 . This value has been determined from experimental data as is known to those skilled in the art. To be within this limit and maintain the flexibility of choosing both alternating magnetic field strength and frequency, it is helpful to be able to adjust both the alternating magnetic field strength and the frequency.
- Embodiments of the present invention provide a number of advantageous features. Firstly, power deposition in the biological systems is limited by the frequency and power of the RF radiation. By varying the power and frequency the system can be tuned to remain inside biologically acceptable limits. Secondly, embodiments of the present invention provide a system which is relatively simple and inexpensive in design which allows it to be purchased and easily serviced. Furthermore, the design circuitry does not require excessive cooling of electronic component parts which makes the circuitry relatively cheap and efficient to manufacture and maintain. Likewise, it is not always necessary to cool the coil.
Landscapes
- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Health & Medical Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Medicinal Chemistry (AREA)
- Pharmacology & Pharmacy (AREA)
- Epidemiology (AREA)
- Life Sciences & Earth Sciences (AREA)
- Animal Behavior & Ethology (AREA)
- General Health & Medical Sciences (AREA)
- Public Health (AREA)
- Veterinary Medicine (AREA)
- Medicines That Contain Protein Lipid Enzymes And Other Medicines (AREA)
- Thermotherapy And Cooling Therapy Devices (AREA)
- Electrotherapy Devices (AREA)
Abstract
Appareil et procédé de chauffage d'un système cible. L'appareil comprend au moins un élément formant bobine, susceptible être placé à proximité du système cible, au moins un élément formant condensateur relié audit au moins un élément formant bobine, une alimentation en courant continu susceptible d'être reliée audit au moins un élément formant bobine par le biais d'un élément de commutation, et un module de commande de commutation servant à mettre sous tension de façon sélective l'élément de commutation à une fréquence souhaitée de manière à chauffer le système cible par chauffage indirect.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB0605672.5 | 2006-03-22 | ||
GB0605672A GB0605672D0 (en) | 2006-03-22 | 2006-03-22 | Indirect heating |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2007107762A1 true WO2007107762A1 (fr) | 2007-09-27 |
Family
ID=36383900
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/GB2007/001020 WO2007107762A1 (fr) | 2006-03-22 | 2007-03-21 | Chauffage indirect |
Country Status (2)
Country | Link |
---|---|
GB (1) | GB0605672D0 (fr) |
WO (1) | WO2007107762A1 (fr) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US9572695B2 (en) | 2009-08-24 | 2017-02-21 | New Phase Ltd | Phase-change and shape-change materials |
US9872902B2 (en) | 2014-11-25 | 2018-01-23 | New Phase Ltd. | Phase-change nanoparticle |
US20180073366A1 (en) * | 2016-09-15 | 2018-03-15 | General Electric Company | Rotational imbalance reduction |
Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE1184413B (de) * | 1961-08-24 | 1964-12-31 | Siemens Ag | Zweistufenschaltung von einphasigen Verbrauchern, z. B. von mit Netzfrequenz gespeisten Induktionsspulen |
US3689726A (en) * | 1971-03-10 | 1972-09-05 | Ajax Magnethermic Corp | Scanning type induction heating |
US4303636A (en) * | 1974-08-20 | 1981-12-01 | Gordon Robert T | Cancer treatment |
US4662359A (en) * | 1983-08-12 | 1987-05-05 | Robert T. Gordon | Use of magnetic susceptibility probes in the treatment of cancer |
EP0295099A2 (fr) * | 1987-06-10 | 1988-12-14 | Yasushi Horiuchi | Dispositif d'alimentation en puissance |
DE4142245A1 (de) * | 1991-12-17 | 1993-06-24 | Tro Transformatoren Und Schalt | Isolierung fuer induktoren von induktiven erhitzungsanlagen und verfahren zu ihrer herstellung |
US5450305A (en) * | 1991-08-12 | 1995-09-12 | Auckland Uniservices Limited | Resonant power supplies |
-
2006
- 2006-03-22 GB GB0605672A patent/GB0605672D0/en not_active Ceased
-
2007
- 2007-03-21 WO PCT/GB2007/001020 patent/WO2007107762A1/fr active Application Filing
Patent Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE1184413B (de) * | 1961-08-24 | 1964-12-31 | Siemens Ag | Zweistufenschaltung von einphasigen Verbrauchern, z. B. von mit Netzfrequenz gespeisten Induktionsspulen |
US3689726A (en) * | 1971-03-10 | 1972-09-05 | Ajax Magnethermic Corp | Scanning type induction heating |
US4303636A (en) * | 1974-08-20 | 1981-12-01 | Gordon Robert T | Cancer treatment |
US4662359A (en) * | 1983-08-12 | 1987-05-05 | Robert T. Gordon | Use of magnetic susceptibility probes in the treatment of cancer |
EP0295099A2 (fr) * | 1987-06-10 | 1988-12-14 | Yasushi Horiuchi | Dispositif d'alimentation en puissance |
US5450305A (en) * | 1991-08-12 | 1995-09-12 | Auckland Uniservices Limited | Resonant power supplies |
DE4142245A1 (de) * | 1991-12-17 | 1993-06-24 | Tro Transformatoren Und Schalt | Isolierung fuer induktoren von induktiven erhitzungsanlagen und verfahren zu ihrer herstellung |
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US9572695B2 (en) | 2009-08-24 | 2017-02-21 | New Phase Ltd | Phase-change and shape-change materials |
US10492935B2 (en) | 2009-08-24 | 2019-12-03 | New Phase Ltd | Phase-change materials |
US9872902B2 (en) | 2014-11-25 | 2018-01-23 | New Phase Ltd. | Phase-change nanoparticle |
US10172939B2 (en) | 2014-11-25 | 2019-01-08 | New Phase Ltd. | Phase-change nanoparticle |
US20180073366A1 (en) * | 2016-09-15 | 2018-03-15 | General Electric Company | Rotational imbalance reduction |
US10309223B2 (en) * | 2016-09-15 | 2019-06-04 | General Electric Company | Rotational imbalance reduction |
Also Published As
Publication number | Publication date |
---|---|
GB0605672D0 (en) | 2006-05-03 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
Christensen et al. | Hyperthermia production for cancer therapy: a rewien of fundamentals and methods | |
US11712368B2 (en) | Medical instrument for in vivo heat source | |
Hand et al. | Heating techniques in hyperthermia | |
US4679561A (en) | Implantable apparatus for localized heating of tissue | |
Strohbehn et al. | Hyperthermia and cancer therapy: A review of biomedical engineering contributions and challenges | |
Mechling et al. | A theoretical comparison of the temperature distributions produced by three interstitial hyperthermia systems | |
Stauffer et al. | Practical induction heating coil designs for clinical hyperthermia with ferromagnetic implants | |
CN104010693A (zh) | 用于产生用于治疗体腔或类似体腔的器官内的癌症的能量场的装置 | |
US8757166B2 (en) | System for defining energy field characteristics to illuminate nano-particles used to treat invasive agents | |
US20140303701A1 (en) | Low Temperature Hyperthermia System for Therapeutic Treatment of Invasive Agents | |
US20110224479A1 (en) | Eddy current induced hyperthermia using conductive particles | |
WO2013114156A1 (fr) | Appareil et procédé d'irradiation de tissu biologique | |
WO2007107762A1 (fr) | Chauffage indirect | |
EP3648693B1 (fr) | Instrument médical pour source de chaleur in vivo | |
WO2011050290A2 (fr) | Systèmes et procédés permettant de réduire le dépôt d'énergie sur un tissu exposé à des champs électromagnétiques à radiofréquence | |
US5412182A (en) | Eddy current heating for hyperthermia cancer treatment | |
Hand | Heat delivery and thermometry in clinical hyperthermia | |
WO2023005719A1 (fr) | Appareil de thérapie par anneau magnétique tridimensionnel et son application | |
Mi et al. | A ns-μs duration, millitesla, exponential decay pulsed magnetic fields generator for tumor treatment | |
Cheung | Microwave and radiofrequency techniques for clinical hyperthermia. | |
US20150157872A1 (en) | Device for Treating Cancer by Hyperthermia and the Method Thereof | |
Singh | Microwave applicators for hyperthermia treatment of cancer: An overview | |
US20230390107A1 (en) | Medical instrument for in vivo heat source | |
CN215900735U (zh) | 三维磁环治疗床 | |
Turner et al. | Technical aspects of hyperthermia |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 07732098 Country of ref document: EP Kind code of ref document: A1 |
|
NENP | Non-entry into the national phase |
Ref country code: DE |
|
122 | Ep: pct application non-entry in european phase |
Ref document number: 07732098 Country of ref document: EP Kind code of ref document: A1 |