GB2213381A - Electro-surgical apparatus with body impedance monitoring - Google Patents

Electro-surgical apparatus with body impedance monitoring Download PDF

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Publication number
GB2213381A
GB2213381A GB8729071A GB8729071A GB2213381A GB 2213381 A GB2213381 A GB 2213381A GB 8729071 A GB8729071 A GB 8729071A GB 8729071 A GB8729071 A GB 8729071A GB 2213381 A GB2213381 A GB 2213381A
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United Kingdom
Prior art keywords
electrodes
current
impedance
value
voltage
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Granted
Application number
GB8729071A
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GB8729071D0 (en
GB2213381B (en
Inventor
Martin Price-Thomas
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University of Wales College of Medicine
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University of Wales College of Medicine
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Priority to GB8729071A priority Critical patent/GB2213381B/en
Publication of GB8729071D0 publication Critical patent/GB8729071D0/en
Publication of GB2213381A publication Critical patent/GB2213381A/en
Application granted granted Critical
Publication of GB2213381B publication Critical patent/GB2213381B/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

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    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B18/00—Surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body
    • A61B18/04—Surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body by heating
    • A61B18/12—Surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body by heating by passing a current through the tissue to be heated, e.g. high-frequency current
    • A61B18/1206—Generators therefor
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00—Measuring for diagnostic purposes; Identification of persons
    • A61B5/05—Detecting, measuring or recording for diagnosis by means of electric currents or magnetic fields; Measuring using microwaves or radio waves 
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B18/00—Surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body
    • A61B2018/00636—Sensing and controlling the application of energy
    • A61B2018/00696—Controlled or regulated parameters
    • A61B2018/00702—Power or energy
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B18/00—Surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body
    • A61B2018/00636—Sensing and controlling the application of energy
    • A61B2018/00773—Sensed parameters
    • A61B2018/00827—Current
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B18/00—Surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body
    • A61B2018/00636—Sensing and controlling the application of energy
    • A61B2018/00773—Sensed parameters
    • A61B2018/00875—Resistance or impedance
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B18/00—Surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body
    • A61B2018/00636—Sensing and controlling the application of energy
    • A61B2018/00773—Sensed parameters
    • A61B2018/00892—Voltage

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  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Surgery (AREA)
  • Engineering & Computer Science (AREA)
  • Public Health (AREA)
  • Molecular Biology (AREA)
  • Veterinary Medicine (AREA)
  • Physics & Mathematics (AREA)
  • Biomedical Technology (AREA)
  • Heart & Thoracic Surgery (AREA)
  • Medical Informatics (AREA)
  • Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
  • General Health & Medical Sciences (AREA)
  • Animal Behavior & Ethology (AREA)
  • Radiology & Medical Imaging (AREA)
  • Biophysics (AREA)
  • Pathology (AREA)
  • Plasma & Fusion (AREA)
  • Otolaryngology (AREA)
  • Surgical Instruments (AREA)

Abstract

Surgical diathermy apparatus including two electrodes to be applied to the patient's body under operation, and means for applying a high-frequency alternating current to the electrodes to perform electro-coagulation or surgery. The equipment also includes means for sensing the instantaneous values of the voltage and current between the electrodes and for calculating the impedance of the total circuit in accordance with these sensed values. An automatic detector senses any impedance value above a pre-determined level and is arranged to produce a warning or control signal. This enables a surgeon to perform delicate, difficult operations even when the operation site is out of view. <IMAGE>

Description

"Surgical Diathermy Instruments" This invention relates to apparatus designed for use in surgical diathermy which expression is intended to include related applications of coagulation and falguration in addition to the direct surgical cutting of tissue. The term "diathermy" as currently used relates to the treatment of the human (or animal) body by heat, the heat being produced or generated directly by flow of electric current through the body. For this purpose it is usually necessary to employ two electrodes and in a typical application there is a large area "neutral" electrode positioned at some point below the body where it is supported, and another "active" electrode of small size which is carefully positioned by the surgeon at the position where diathermy is needed.
The electric current is normally relatively high-frequency and may be within various different a ranges, for example between about 300 and 3,000 kHz or up to 3 mGh or 5 mGh. The higher frequencies are usually employed for surgical operations involving the cutting of tissue.
Electro-coagulation is frequently employed in all surgical operations to close off severed blood vessels for haemostasis. Falguration is a modified form of this haemostasis procedure which involves a degree of charring of the tissue with deep necrosis.
Surgical diathermy is particularly advantageous in certain types of surgical operation and one procedure in particular is of major interest, trans-urethral resection of the prostrate (T.U.R.). This involves the use of an electrosurgical diathermy cutting "loop" introduced into the bladder via a cystoscope, the bladder being filled and flushed with a low conductivity fluid.
It is important that only prostrate tissue is cut into during the resection, and that the tissue of the surrounding capsule is not cut. Should this occur blood vessels which pass through the capsule tend to retract back into this tissue and the bleeding is hard to stop. Longer hospitalisation is then necessary and additional blood transfusions may be required with their attendant risks.
At certain times during the procedure the exact point of application of the cutting loop may of necessity be out of view of the surgeon and skill and experience are important factors in ensuring a successful outcome. "Nevertheless, even in experienced hands, cutting of the capsule can occur.
It is an object of the invention accordingly to provide an improved form of diathermy apparatus which will assist the surgeon in carrying out delicate or difficult surgical procedures such as T-.U.R.
The invention is based on the appreciation that there are variations in the electrical impedance in different parts of the body and by sensing changes in the impedance sensitively and rapidly it may be possible to give the surgeon warning or to cut off or reduce the electrical current to the electrodes automatically. Obviously this can be of benefit especially when the surgeon is unable to see the electrode directly.
Broadly stated the invention consists in surgical diathermy apparatus comprising two electrodes or probes to be applied to the body under operation and means for supplying an alternating current to the electrodes, with means for sensing the impedance of the body between the electrodes, and a sensor for detecting any value or change in impedance above a determined level and for producing a warning or control signal. Since the impedance cannot normally be sensed directly the apparatus preferably includes means for calculating the impedance in accordance with the voltage and current between the electrodes.
Since the current is alternating at a high frequency the apparatus also preferably includes means for detecting the R.M.S. value of the voltage and/or current between the electrodes.
The apparatus may include means for maintaining a substantially constant voltage supply across the electrodes and means for sensing the value of the current flowing. In such case the apparatus itself will not normally include means for measuring the voltage.
In any case the apparatus is preferably arranged to generate an audible or visual alarm and/or a warning display. For example there may be a visual warning display adjacent the active electrode.
According to another preferred feature of the invention the apparatus includes a highspeed electrical switch in the circuit of the electrodes and means for automatically opening or adjusting the switch circuit in response to a predetermined change in the sensed impedance so as to shut off or modify the current in the electrode.
The invention may be performed in various ways and one particular embodiment will now be described, by way of example, with reference to the accompanying drawing which is a diagrammatic illustration of a surgical diathermy unit according to the invention.
In this illustration the patient 2 is shown lying on a table with the neutral electrode 4 below and the active electrode or cutting loop 3 above.
The electrode surgical unit 1 is in effect a radiofrequency generator capable of supplying current at the required frequency and voltage to the electrode leads of terminals A or N. The actual frequency may vary considerably as outlined above and different frequencies may be used for different purposes.
Accordingly the unit will normally include a frequency changing switch. It may also be required to alter the voltage and current supplied to the electrodes and voltage and current control devices will also be incorporated. Alternatively, or in addition, there may be devices to maintain a preselected value of current or voltage, especially a constant voltage supply control. The power generating unit is connected to amainssupply, but will incorporate isolating or insulating systems so that the electrode voltage is "floating" and the patient is not at risk of being exposed to mains voltage.
In this particular example the system includes a voltage measuring device 6, and a current measuring device 5 in one of the leads, these two devices being connected into a control unit 7, which includes a calculating or processing section for deriving the instantaneous value of the impedance between the electrodes based on the measured current and voltage. Since the electrode current is of very high frequency it is important that these measured values should be R.M.S. (Root Mean Square). The control unit 7 is arranged to operate a warning or trip circuit which will automatically energise a warning display or an audible or visual alarm.
The visual alarm may, for example, be incorporated into the actual active electrode 3 so as to be immediately visible to the surgeon. Alternatively, or in addition, the control circuit 7 may be arranged to actuate a switch 8 to open the electrode circuit and immediately cut off the electrode current.
The value at which the automatic circuit "triggers" may vary in accordance with a number of different parameters. For example, the applied frequency or voltage of the power unit 1, or the particular part of the body under operation may result in different impedance values and different settings of the "trigger" value.
It may be possible to obtain a useful indication of changes of body impedance by means other than direct voltage or current measuring or sensing devices. For example, an accurate high-speed power detector sensing the energy in the electrode circuit will react quickly to changes in impedance.

Claims (7)

CLAIMS 1. Surgical diathermy apparatus comprising two electrodes or probes to be applied to the body under operation and means for supplying an alternating current to the electrodes, with means for sensing the impedance of the body between the electrodes, and a sensor for detecting any value or change in impedance above a determined level and for producing a warning or control signal. 2. Apparatus according to Claim 1, including means for calculating the impedance in accordance with the voltage and current between the electrodes. 3. Apparatus according to Claim 2, including means for detecting the R.M.S. value of the voltage and/or current between the electrodes. 4. Apparatus according to any of the preceding claims, including means for maintaining a substantially constant voltage supply across the electrodes and means for sensing the value of the current flowing. 5. Apparatus according to any of the preceding claims, in which the apparatus is arranged to generate an audible or visual alarm and/or a warning display. 6. Apparatus according to Claim 5, in which the equipment includes a visual warning display adjacent the active electrode. 7. Apparatus according to any of the preceding claims, including a high-speed electrical switch in the circuit of the electrodes and means for automatically opening or adjusting the switch circuit in response to a predetermined change in the sensed impedance so as to shut off or modify the current in the electrode. 7. Surgical diathermy apparatus substantially in any of the forms described with reference to the accompanying drawings. Amendments to the claims have been filed as follows
1. Surgical diathermy apparatus comprising two electrodes or probes to be applied to the body under operation and means for supplying an alternating current to the electrodes, with means for sensing the impedance of the body between the electrodes, and a sensor for detecting any value or change in impedance above a determined level and for producing a warning or control signal.
2. Apparatus according to Claim 1, including means for calculating the impedance in accordance with the voltage and current between the electrodes.
3. Apparatus according to Claim 2, including means for detecting the R.M.S. value of the voltage and/or current between the electrodes.
4. Apparatus according to any of the preceding claims, including means for maintaining a substantially constant voltage supply across the electrodes and means for sensing the value of the current flowing.
5. Apparatus according to any of the preceding claims, in which the apparatus is arranged to generate an audible or visual alarm and/or a warning display.
6. Apparatus according to Claim 5, in which the equipment includes a visual warning display adjacent the active electrode.
7. Surgical diathermy apparatus substantially in any of the forms described with reference to the accompanying drawings.
7. Apparatus according to any of the preceding claims, including a high-speed electrical switch in the circuit of the electrodes and means for automatically opening or adjusting the switch circuit in response to a predetermined change in the sensed impedance so as to shut off or modify the current in the electrode.
GB8729071A 1987-12-12 1987-12-12 Surgical diathermy instruments Expired - Fee Related GB2213381B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB8729071A GB2213381B (en) 1987-12-12 1987-12-12 Surgical diathermy instruments

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB8729071A GB2213381B (en) 1987-12-12 1987-12-12 Surgical diathermy instruments

Publications (3)

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GB8729071D0 GB8729071D0 (en) 1988-01-27
GB2213381A true GB2213381A (en) 1989-08-16
GB2213381B GB2213381B (en) 1992-06-03

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Family Applications (1)

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GB8729071A Expired - Fee Related GB2213381B (en) 1987-12-12 1987-12-12 Surgical diathermy instruments

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Cited By (33)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5078714A (en) * 1990-03-02 1992-01-07 Jefferson Katims Method and apparatus for placement of a probe in the body and the medical procedure for guiding and locating a catheter or probe in the body
EP0495140A1 (en) * 1991-01-16 1992-07-22 Erbe Elektromedizin GmbH H.F. electrosurgical unit
EP0517243A1 (en) * 1991-06-07 1992-12-09 Hemostatic Surgery Corporation High frequency electrosurgical apparatus employing constant voltage and methods of use
WO1993009725A1 (en) * 1990-03-02 1993-05-27 Katims Jefferson J Method and apparatus for guiding a catheter
EP0556705A1 (en) * 1992-02-20 1993-08-25 DELMA ELEKTRO-UND MEDIZINISCHE APPARATEBAU GESELLSCHAFT mbH High frequency surgery device
EP0566726A1 (en) * 1991-11-08 1993-10-27 Ep Technologies, Inc. Systems and methods for ablating tissue while monitoring tissue impedance
WO1994010925A1 (en) * 1992-11-13 1994-05-26 American Cardiac Ablation Co., Inc. Fluid cooled electrosurgical cauterization system
FR2706041A1 (en) * 1993-06-01 1994-12-09 Conmed Corp Current detector for medical devices including connection cables.
WO1995003743A1 (en) * 1993-07-27 1995-02-09 Valleylab, Inc. Apparatus for esu leakage current control and relevant method
US5423810A (en) * 1992-02-27 1995-06-13 G2 Design Limited Cauterising apparatus
US5472443A (en) * 1991-06-07 1995-12-05 Hemostatic Surgery Corporation Electrosurgical apparatus employing constant voltage and methods of use
EP0696181A1 (en) * 1993-04-30 1996-02-14 Medical Scientific, Inc. Impedance feedback electrosurgical system
GB2267829B (en) * 1992-06-19 1996-04-24 Conmed Corp Electrosurgical system
US5540684A (en) * 1994-07-28 1996-07-30 Hassler, Jr.; William L. Method and apparatus for electrosurgically treating tissue
US5558671A (en) * 1993-07-22 1996-09-24 Yates; David C. Impedance feedback monitor for electrosurgical instrument
US5633578A (en) * 1991-06-07 1997-05-27 Hemostatic Surgery Corporation Electrosurgical generator adaptors
US5688266A (en) * 1991-11-08 1997-11-18 Ep Technologies, Inc. Electrode and associated systems using thermally insulated temperature sensing elements
US5693051A (en) * 1993-07-22 1997-12-02 Ethicon Endo-Surgery, Inc. Electrosurgical hemostatic device with adaptive electrodes
US5693045A (en) * 1995-06-07 1997-12-02 Hemostatic Surgery Corporation Electrosurgical generator cable
US5713896A (en) * 1991-11-01 1998-02-03 Medical Scientific, Inc. Impedance feedback electrosurgical system
US5722975A (en) * 1991-11-08 1998-03-03 E.P. Technologies Inc. Systems for radiofrequency ablation with phase sensitive power detection and control
US5743903A (en) * 1991-11-08 1998-04-28 Ep Technologies, Inc. Cardiac ablation systems and methods using tissue temperature monitoring and control
US5807393A (en) * 1992-12-22 1998-09-15 Ethicon Endo-Surgery, Inc. Surgical tissue treating device with locking mechanism
US5817093A (en) * 1993-07-22 1998-10-06 Ethicon Endo-Surgery, Inc. Impedance feedback monitor with query electrode for electrosurgical instrument
US5817091A (en) * 1997-05-20 1998-10-06 Medical Scientific, Inc. Electrosurgical device having a visible indicator
WO1999021475A1 (en) * 1997-10-24 1999-05-06 Pulsion Medical Systems Gmbh Device for detecting pericardial effusion
US5919191A (en) * 1995-01-30 1999-07-06 Boston Scientific Corporation Electro-surgical tissue removal
US6454765B1 (en) 1995-03-24 2002-09-24 The Board Of Regents Of The University Of Nebraska Methods for volumetric tissue ablation
US6575967B1 (en) 1995-03-24 2003-06-10 The Board Of Regents Of The University Of Nebraska Method and systems for volumetric tissue ablation
US6671550B2 (en) 2000-09-20 2003-12-30 Medtronic, Inc. System and method for determining location and tissue contact of an implantable medical device within a body
US6714806B2 (en) 2000-09-20 2004-03-30 Medtronic, Inc. System and method for determining tissue contact of an implantable medical device within a body
US20090234351A1 (en) * 2004-08-20 2009-09-17 Kai Desinger Device for the Electro-Surgical Sclerosing of body tissues
EP3053536A1 (en) * 2014-12-19 2016-08-10 Brera Medical Technologies S.r.l. Electronic device for diathermy with active control of current

Families Citing this family (13)

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Publication number Priority date Publication date Assignee Title
US6015406A (en) 1996-01-09 2000-01-18 Gyrus Medical Limited Electrosurgical instrument
US6293942B1 (en) 1995-06-23 2001-09-25 Gyrus Medical Limited Electrosurgical generator method
EP1050278A1 (en) 1995-06-23 2000-11-08 Gyrus Medical Limited An electrosurgical instrument
IL122713A (en) 1995-06-23 2001-04-30 Gyrus Medical Ltd Electrosurgical instrument
US6780180B1 (en) 1995-06-23 2004-08-24 Gyrus Medical Limited Electrosurgical instrument
US6090106A (en) 1996-01-09 2000-07-18 Gyrus Medical Limited Electrosurgical instrument
US6013076A (en) 1996-01-09 2000-01-11 Gyrus Medical Limited Electrosurgical instrument
US6565561B1 (en) 1996-06-20 2003-05-20 Cyrus Medical Limited Electrosurgical instrument
GB9612993D0 (en) 1996-06-20 1996-08-21 Gyrus Medical Ltd Electrosurgical instrument
GB2314274A (en) 1996-06-20 1997-12-24 Gyrus Medical Ltd Electrode construction for an electrosurgical instrument
GB9626512D0 (en) 1996-12-20 1997-02-05 Gyrus Medical Ltd An improved electrosurgical generator and system
US6494881B1 (en) 1997-09-30 2002-12-17 Scimed Life Systems, Inc. Apparatus and method for electrode-surgical tissue removal having a selectively insulated electrode
GB9807303D0 (en) 1998-04-03 1998-06-03 Gyrus Medical Ltd An electrode assembly for an electrosurgical instrument

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GB855459A (en) * 1958-04-11 1960-11-30 Keeler Optical Products Ltd Improvements in or relating to electro-surgical apparatus
US3933157A (en) * 1973-10-23 1976-01-20 Aktiebolaget Stille-Werner Test and control device for electrosurgical apparatus
US4372315A (en) * 1980-07-03 1983-02-08 Hair Free Centers Impedance sensing epilator
US4416277A (en) * 1981-11-03 1983-11-22 Valleylab, Inc. Return electrode monitoring system for use during electrosurgical activation
US4416276A (en) * 1981-10-26 1983-11-22 Valleylab, Inc. Adaptive, return electrode monitoring system
EP0136855A2 (en) * 1983-09-13 1985-04-10 Valleylab, Inc. Electrosurgical generator

Family Cites Families (1)

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US4727874A (en) * 1984-09-10 1988-03-01 C. R. Bard, Inc. Electrosurgical generator with high-frequency pulse width modulated feedback power control

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB855459A (en) * 1958-04-11 1960-11-30 Keeler Optical Products Ltd Improvements in or relating to electro-surgical apparatus
US3933157A (en) * 1973-10-23 1976-01-20 Aktiebolaget Stille-Werner Test and control device for electrosurgical apparatus
US4372315A (en) * 1980-07-03 1983-02-08 Hair Free Centers Impedance sensing epilator
US4416276A (en) * 1981-10-26 1983-11-22 Valleylab, Inc. Adaptive, return electrode monitoring system
US4416277A (en) * 1981-11-03 1983-11-22 Valleylab, Inc. Return electrode monitoring system for use during electrosurgical activation
EP0136855A2 (en) * 1983-09-13 1985-04-10 Valleylab, Inc. Electrosurgical generator

Cited By (43)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5078714A (en) * 1990-03-02 1992-01-07 Jefferson Katims Method and apparatus for placement of a probe in the body and the medical procedure for guiding and locating a catheter or probe in the body
WO1993009725A1 (en) * 1990-03-02 1993-05-27 Katims Jefferson J Method and apparatus for guiding a catheter
EP0495140A1 (en) * 1991-01-16 1992-07-22 Erbe Elektromedizin GmbH H.F. electrosurgical unit
US5267997A (en) * 1991-01-16 1993-12-07 Erbe Elektromedizin Gmbh High-frequency electrosurgery apparatus with limitation of effective value of current flowing through a surgical instrument
EP0517243A1 (en) * 1991-06-07 1992-12-09 Hemostatic Surgery Corporation High frequency electrosurgical apparatus employing constant voltage and methods of use
US5633578A (en) * 1991-06-07 1997-05-27 Hemostatic Surgery Corporation Electrosurgical generator adaptors
US5472443A (en) * 1991-06-07 1995-12-05 Hemostatic Surgery Corporation Electrosurgical apparatus employing constant voltage and methods of use
US5713896A (en) * 1991-11-01 1998-02-03 Medical Scientific, Inc. Impedance feedback electrosurgical system
US5743903A (en) * 1991-11-08 1998-04-28 Ep Technologies, Inc. Cardiac ablation systems and methods using tissue temperature monitoring and control
EP0566726A1 (en) * 1991-11-08 1993-10-27 Ep Technologies, Inc. Systems and methods for ablating tissue while monitoring tissue impedance
US5722975A (en) * 1991-11-08 1998-03-03 E.P. Technologies Inc. Systems for radiofrequency ablation with phase sensitive power detection and control
US5897552A (en) * 1991-11-08 1999-04-27 Ep Technologies, Inc. Electrode and associated systems using thermally insulated temperature sensing elements
US5688266A (en) * 1991-11-08 1997-11-18 Ep Technologies, Inc. Electrode and associated systems using thermally insulated temperature sensing elements
EP0566726A4 (en) * 1991-11-08 1994-03-16 Ep Technologies, Inc.
EP0556705A1 (en) * 1992-02-20 1993-08-25 DELMA ELEKTRO-UND MEDIZINISCHE APPARATEBAU GESELLSCHAFT mbH High frequency surgery device
US5423810A (en) * 1992-02-27 1995-06-13 G2 Design Limited Cauterising apparatus
GB2267829B (en) * 1992-06-19 1996-04-24 Conmed Corp Electrosurgical system
US5437662A (en) * 1992-11-13 1995-08-01 American Cardiac Ablation Co., Inc. Fluid cooled electrosurgical cauterization system
US5342357A (en) * 1992-11-13 1994-08-30 American Cardiac Ablation Co., Inc. Fluid cooled electrosurgical cauterization system
WO1994010925A1 (en) * 1992-11-13 1994-05-26 American Cardiac Ablation Co., Inc. Fluid cooled electrosurgical cauterization system
US5807393A (en) * 1992-12-22 1998-09-15 Ethicon Endo-Surgery, Inc. Surgical tissue treating device with locking mechanism
EP0696181A1 (en) * 1993-04-30 1996-02-14 Medical Scientific, Inc. Impedance feedback electrosurgical system
EP0696181A4 (en) * 1993-04-30 1996-11-06 Medical Scient Inc Impedance feedback electrosurgical system
EP0696182A4 (en) * 1993-04-30 1996-11-06 Medical Scient Inc Impedance feedback electrosurgical system
FR2706041A1 (en) * 1993-06-01 1994-12-09 Conmed Corp Current detector for medical devices including connection cables.
US5693051A (en) * 1993-07-22 1997-12-02 Ethicon Endo-Surgery, Inc. Electrosurgical hemostatic device with adaptive electrodes
US5558671A (en) * 1993-07-22 1996-09-24 Yates; David C. Impedance feedback monitor for electrosurgical instrument
US5817093A (en) * 1993-07-22 1998-10-06 Ethicon Endo-Surgery, Inc. Impedance feedback monitor with query electrode for electrosurgical instrument
WO1995003743A1 (en) * 1993-07-27 1995-02-09 Valleylab, Inc. Apparatus for esu leakage current control and relevant method
US5540684A (en) * 1994-07-28 1996-07-30 Hassler, Jr.; William L. Method and apparatus for electrosurgically treating tissue
US5919191A (en) * 1995-01-30 1999-07-06 Boston Scientific Corporation Electro-surgical tissue removal
US6454765B1 (en) 1995-03-24 2002-09-24 The Board Of Regents Of The University Of Nebraska Methods for volumetric tissue ablation
US6468273B1 (en) 1995-03-24 2002-10-22 The Board Of Regents Of The University Of Nebraska Methods for volumetric tissue ablation
US6575967B1 (en) 1995-03-24 2003-06-10 The Board Of Regents Of The University Of Nebraska Method and systems for volumetric tissue ablation
US5693045A (en) * 1995-06-07 1997-12-02 Hemostatic Surgery Corporation Electrosurgical generator cable
US5817091A (en) * 1997-05-20 1998-10-06 Medical Scientific, Inc. Electrosurgical device having a visible indicator
WO1999021475A1 (en) * 1997-10-24 1999-05-06 Pulsion Medical Systems Gmbh Device for detecting pericardial effusion
US6351667B1 (en) 1997-10-24 2002-02-26 Pulsion Medical Systems Ag Device for detecting pericardial effusion
US6671550B2 (en) 2000-09-20 2003-12-30 Medtronic, Inc. System and method for determining location and tissue contact of an implantable medical device within a body
US6714806B2 (en) 2000-09-20 2004-03-30 Medtronic, Inc. System and method for determining tissue contact of an implantable medical device within a body
US20090234351A1 (en) * 2004-08-20 2009-09-17 Kai Desinger Device for the Electro-Surgical Sclerosing of body tissues
US8221406B2 (en) * 2004-08-20 2012-07-17 Celon Ag Medical Instruments Device for the electro-surgical sclerosing of body tissues
EP3053536A1 (en) * 2014-12-19 2016-08-10 Brera Medical Technologies S.r.l. Electronic device for diathermy with active control of current

Also Published As

Publication number Publication date
GB8729071D0 (en) 1988-01-27
GB2213381B (en) 1992-06-03

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Effective date: 20001212