CA1077366A - Surgical instrument having self-regulated electrical skin-depth heating of its cutting edge and method of using the same - Google Patents
Surgical instrument having self-regulated electrical skin-depth heating of its cutting edge and method of using the sameInfo
- Publication number
- CA1077366A CA1077366A CA246,546A CA246546A CA1077366A CA 1077366 A CA1077366 A CA 1077366A CA 246546 A CA246546 A CA 246546A CA 1077366 A CA1077366 A CA 1077366A
- Authority
- CA
- Canada
- Prior art keywords
- cutting edge
- conductor means
- electrical conductor
- blade
- electrical
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- 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
- A61B18/14—Probes or electrodes therefor
-
- 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
- A61B18/08—Surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body by heating by means of electrically-heated probes
-
- 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
- A61B2018/00053—Mechanical features of the instrument of device
- A61B2018/00107—Coatings on the energy applicator
Abstract
SURGICAL INSTRUMENT HAVING SELF-REGULATED
ELECTRICAL SKIN-DEPTH HEATING OF ITS CUTTING
EDGE AND METHOD OF USING THE SAME
Abstract of the Disclosure The cutting edge of a scalpel blade is resistively heated to a preselected constant temperature range by conduction of high frequency electrical currents within variable skin depths of a ferromagnetic conductor that is disposed on the blade in the region of the cutting edge.
ELECTRICAL SKIN-DEPTH HEATING OF ITS CUTTING
EDGE AND METHOD OF USING THE SAME
Abstract of the Disclosure The cutting edge of a scalpel blade is resistively heated to a preselected constant temperature range by conduction of high frequency electrical currents within variable skin depths of a ferromagnetic conductor that is disposed on the blade in the region of the cutting edge.
Description
`3~
Background of the Invention The control of bleeding during surgery accounts for a major portion of the total time involved in an operation. The bleeding that occurs from the plethora of small blood vessels that pervade all tissues whenever tissues are incised obscures the surgeon's vision, reduces his precision, and often dictates slow and elaborate procedures in surgical operations. It is well known to heat the tissues to minimize bleeding from in-cisions, and surgical scalpels which are designed to elevate tissue temperatures and minimize bleeding are also well known~
One such scalpel transmits high frequency, high energy sparks from a small electrode held in the surgeon's hand to the tissues, where they are converted to heat. Typically, substantial elec-trical currents pass through the patient's body to a large electrode beneath the patient, which completes the electrical circuit. Discharge of sparks and temperature conversion in the tissue are poorly controlled in distribution and intensity, and erratic muscular contractions in the patient are produced so that this apparatus cannot be used to perform precise surgery.
Further, apparatus of this type frequently produce severe tissue damage and debris in the form of charred and dead tissue, which ;~
materially interfere with wound healing.
.... . . . .. .
... , - , - , .
. ,.. . :
:~7~3~;t;
Another well-known surgical scalpel employs a blade with a resistive heating element which cuts the tissue and pro-vides simultaneous hemostasis. Although these resistive elements can be readily brought to a suitably high and constant temperature in air prior to contacting tissues, as soon as portions of the blade come in contact with tissues, they are rapidly cooled.
During surgery, non-predictable and continuously varying portions of the blade contact the tissues as they are being cut. AS the blade cools, the tissue cutting and hemostasis become markedly less effective and tissue tends to adhere to the blade. If additional power is applied by conventional means to counteract this cooling, this additional power is selectively delivered to the uncooled portions of the blade, frequently resulting in excessive temperatures which may result in tissue damage and blade destruction. This results from the fact that in certain known resistively heated scalpels, the heating is a function of the current squared times the resistance (I2R). In conventional metallic blades of this type, the higher the temperature of any blade portion, the greater its electrical resistance, and con-sequently the greater the incremental heating resulting fromincremental power input.
It is generally recognized that to seal tissues and effect hemostasis it is desirable to operate at a temperature be-tween 300C. and 1000C. And for reasons noted above, it is de-sirable that electrothermal hemostatic surgical cutting instru-ments include a mechanism by which power is selectively delivered to those portions of the blade that are cooled by tissue contact so that the cutting edge may be maintained at a substantially uniform operating temperature within the desired optimal range. Recently, hemostatic scalpels have been described 1~7'73~
(see, for example, U. S. Patents 3,768,~2 and 3,826,263) in which -the temperature-controlling mechanisms include resis-tive heating elements disposed on the surface of the scalpel blade. However, such instruments require precision in fabricat-ing the dimensions of the heating elements to obtain the desired resistances. And such resistive heating elements may be subjected to variations in resistance during use, as tissue juices and proteins become deposited upon the surface- of the blade.
Summary of the Invention In accordance with one aspect of this invention there is provided a blade comprising: a cutting means including a cutting edge; and electrical conductor means disposed near said cutting edge, said electrical conductox means including a material being capable of varying the skin depth of the conduction path for alternating electrical ~urrent there-through; and a source of radio frequency electrical current, said source being connected to said electrical conductor means for supplying radio-frequency electrical current thereto.
In accordance with another aspect of this invention there is provided the method of cutting using a blade means having a cutting edge operating at an elevated temperature, ~`
the method comprising: applying an alternating electrical current in a conduction path to heat the cutting edge; and selectively increasing the heating of the cutting edge by decreasing the skin depth of the conduction path in regions thereof that are cooled, while cutting with said blade means. ~!
By way of added explanation, the present invention provides a surg;cal cutting instrument in which the cutting portion o~ the blade is brought to and maintained within an elevated preselected temperature range by heating due to radio frequency electrical current flowing within 1C~773~
variable skin dep-ths in an electrical conductor disposed in the region of the cutting eclge. Radio frequency alternating current is conducted by the current-carrying conductor dis-posed near the cutting edge of the blade. The current tends to concentrate near the surface and to attenuate exponentially ~ith distance from the surface. This phenomenon is called "skin effect". The depth of this skin effect is the depth at which the current is reduced to a]bout 37~ of its surface value and is determined by the electrical resistivity and magnetic permeability of the material conducting the current and by the frequency of the alternating current. The skin depth d, in centimeters, is determined by d a 5 (103) ~/ ~f' ~
where p is electrical resistivity in ohm-centimeters, ~ is relative magnetic permeability, and f is frequency in hertz.
-3a-e~
.
73~it;
~ self-regulating heated scalpel is constructed by causing radio frequency (RF) curren-t to flow in conductors utilized as resistive heating elements which are disposed in the region of the cutting edge of the scalpel and which are con-structed of a material that exhibits an increase in an electrical parameter such as magnetic permeability as the temperature de-creases. It can be seen that an increase in magnetic permeability causes a decrease in the skin depth. Since the resistance of the current-conducting path is inversely proportional to cross-sectional area (path width times skin depth), this ef~ect causesan increase in the resistance of the current path in cooled regions and an increase in the Joule heating thereof.
By way of example, ferromagnetic material such as iron, nickel, and cobalt, and their alloys exhibit large changes in relative permeability as their temperature goes through a tran-sition point called the "Curie" point. For many iron-nickel alloys this Curie point occurs at about 450C., above which the ~ -relative permeability is near unity and below which it is high, perhaps 100 to 1000, for the magnetic field strengths that would be utilized in this application. An applied RF signal causes current to flow in the surface conductor of the blade near the ;
cutting edge which heats the edge to about 500C. prior to con-tact with tissues. When portions of the cutting edge are cooled upon contact with tissues, the cooled portions may drop in temperature below the Curie point and this will increase the relative permeability from near unity to above 100. mhe asso-ciated skin depth will decrease more than 10 to 1 and heating will increase proportionately in the cooled portion.
In accordance with the present invention, a scalpel blade of electrically insulating material such as alumina ~7'736~
ceramic is electrically heated in the region of the cutting edge thereof by conducting high frequency current along con~
ductors near the cutting edge, which conductors are formed of ferromagnetic material disposed on the insulating material of the blade.
Description of the Drawings Figure 1 is a side view of the surgical instrument according to the present invention; and Figure 2 is an end sectional view of the blade of the apparatus of Figure 1.
Description of the Preferred Embodiment _ _ Referring now to Figures 1 and 2 there is shown one embodiment of the present invention including a blade portion 9 of electrically insulating material such as alumina ceramic attached to a handle portion 11 to form the surgical instrument.
A signal conductor 13 of ferromagnetic material such as nickel-iron is disposed on the blade 9 adjacent the cutting edge 21 to form a complete conduction path along one side of the blade 9 and back along the other side of the blade. Input power at radio frequencies may be supplied to the conductor 13 from power source 19 through connection means 15 and 17.
With the current-carrying conductor 9 formed of ferromagnetic material, the skin depth characteristic pre-viously discussed can be utilized advantageously for temper-ature regulation. Current flowing through the ferromagnetic conductor 13 will flow on the inside of the conductor at the skin depth for the material and heat the ferromagnetic ma-terial and the ceramic cutting edge 21 thermally coupled thereto. From an operating temperature in air which is above the Curie temperature, portions of the cutting edge will cool -~; ,. :
1~'7736Ei as it touches tissue and its operating temperature may drop below the Curie temperature and the skin depth will decrease about 10 to 1 giving approximately a 10 to 1 local increase in heating. To achieve a 10 to 1 power increase, not only must the relative permeability increase 100 to 1 when cooled by tissue contact, but also the skin depth at pre-cutting operative con-ditions in air must be approximately two-thirds the thickness of the conductor or less in order to realize the 10 to 1 skin depth reduction. Thus, for a suitably thin scalpel blade with a suitably thin ferromagnetic self-regulating conductive heater disposed upon it, high frequencies may be required to establish the requisite skin depths. The following tabulation shows the frequency required for various skin depths above and below the Curie point in a 50:50 iron-nickel ferromagnetic alloy and shows the relative power dissipation o~ a 40 mil wide conductor dis-posed continuously upon both facets of a scalpel blade in the region of a 3 cm. cutting edge when energized by a current of about 3 amperes:
Temper- Permea- Skin ature Resistivity bility Frequency Depth Resistance Power C. ohms-cm(10 6) MHz mils ohms watts/cm (inch 3 of cutting x 10 _) edge 500 105 1 6 8.3 .29 .88 500 105 1 20 4.5 .54 1.61 500 105 1 100 2.0 1.20 3.Sl 400 100 100 6 0.81 2.87 8.62 400 100 100 20 0.44 5.25 15.7 28 400 100 100 100 0.20 11.7 35.2 _ :: : - ,. . . .
. ' ' ' ' ~
1(~'773f~
A layer of insulation 23 is disposed over the conductors 13 to insulate the tissue being cut from the electrical currents.
The high frequency signal source 19 may be adjustable in signal amplitude or in frequency, or both, to adjust the average operating temperature of the cutting edge. The fre-quency may be adjusted to alter the skin depth, as described above, and thereby to establish the ambient operating temperature 8 of the cutting edge in air.
..
Background of the Invention The control of bleeding during surgery accounts for a major portion of the total time involved in an operation. The bleeding that occurs from the plethora of small blood vessels that pervade all tissues whenever tissues are incised obscures the surgeon's vision, reduces his precision, and often dictates slow and elaborate procedures in surgical operations. It is well known to heat the tissues to minimize bleeding from in-cisions, and surgical scalpels which are designed to elevate tissue temperatures and minimize bleeding are also well known~
One such scalpel transmits high frequency, high energy sparks from a small electrode held in the surgeon's hand to the tissues, where they are converted to heat. Typically, substantial elec-trical currents pass through the patient's body to a large electrode beneath the patient, which completes the electrical circuit. Discharge of sparks and temperature conversion in the tissue are poorly controlled in distribution and intensity, and erratic muscular contractions in the patient are produced so that this apparatus cannot be used to perform precise surgery.
Further, apparatus of this type frequently produce severe tissue damage and debris in the form of charred and dead tissue, which ;~
materially interfere with wound healing.
.... . . . .. .
... , - , - , .
. ,.. . :
:~7~3~;t;
Another well-known surgical scalpel employs a blade with a resistive heating element which cuts the tissue and pro-vides simultaneous hemostasis. Although these resistive elements can be readily brought to a suitably high and constant temperature in air prior to contacting tissues, as soon as portions of the blade come in contact with tissues, they are rapidly cooled.
During surgery, non-predictable and continuously varying portions of the blade contact the tissues as they are being cut. AS the blade cools, the tissue cutting and hemostasis become markedly less effective and tissue tends to adhere to the blade. If additional power is applied by conventional means to counteract this cooling, this additional power is selectively delivered to the uncooled portions of the blade, frequently resulting in excessive temperatures which may result in tissue damage and blade destruction. This results from the fact that in certain known resistively heated scalpels, the heating is a function of the current squared times the resistance (I2R). In conventional metallic blades of this type, the higher the temperature of any blade portion, the greater its electrical resistance, and con-sequently the greater the incremental heating resulting fromincremental power input.
It is generally recognized that to seal tissues and effect hemostasis it is desirable to operate at a temperature be-tween 300C. and 1000C. And for reasons noted above, it is de-sirable that electrothermal hemostatic surgical cutting instru-ments include a mechanism by which power is selectively delivered to those portions of the blade that are cooled by tissue contact so that the cutting edge may be maintained at a substantially uniform operating temperature within the desired optimal range. Recently, hemostatic scalpels have been described 1~7'73~
(see, for example, U. S. Patents 3,768,~2 and 3,826,263) in which -the temperature-controlling mechanisms include resis-tive heating elements disposed on the surface of the scalpel blade. However, such instruments require precision in fabricat-ing the dimensions of the heating elements to obtain the desired resistances. And such resistive heating elements may be subjected to variations in resistance during use, as tissue juices and proteins become deposited upon the surface- of the blade.
Summary of the Invention In accordance with one aspect of this invention there is provided a blade comprising: a cutting means including a cutting edge; and electrical conductor means disposed near said cutting edge, said electrical conductox means including a material being capable of varying the skin depth of the conduction path for alternating electrical ~urrent there-through; and a source of radio frequency electrical current, said source being connected to said electrical conductor means for supplying radio-frequency electrical current thereto.
In accordance with another aspect of this invention there is provided the method of cutting using a blade means having a cutting edge operating at an elevated temperature, ~`
the method comprising: applying an alternating electrical current in a conduction path to heat the cutting edge; and selectively increasing the heating of the cutting edge by decreasing the skin depth of the conduction path in regions thereof that are cooled, while cutting with said blade means. ~!
By way of added explanation, the present invention provides a surg;cal cutting instrument in which the cutting portion o~ the blade is brought to and maintained within an elevated preselected temperature range by heating due to radio frequency electrical current flowing within 1C~773~
variable skin dep-ths in an electrical conductor disposed in the region of the cutting eclge. Radio frequency alternating current is conducted by the current-carrying conductor dis-posed near the cutting edge of the blade. The current tends to concentrate near the surface and to attenuate exponentially ~ith distance from the surface. This phenomenon is called "skin effect". The depth of this skin effect is the depth at which the current is reduced to a]bout 37~ of its surface value and is determined by the electrical resistivity and magnetic permeability of the material conducting the current and by the frequency of the alternating current. The skin depth d, in centimeters, is determined by d a 5 (103) ~/ ~f' ~
where p is electrical resistivity in ohm-centimeters, ~ is relative magnetic permeability, and f is frequency in hertz.
-3a-e~
.
73~it;
~ self-regulating heated scalpel is constructed by causing radio frequency (RF) curren-t to flow in conductors utilized as resistive heating elements which are disposed in the region of the cutting edge of the scalpel and which are con-structed of a material that exhibits an increase in an electrical parameter such as magnetic permeability as the temperature de-creases. It can be seen that an increase in magnetic permeability causes a decrease in the skin depth. Since the resistance of the current-conducting path is inversely proportional to cross-sectional area (path width times skin depth), this ef~ect causesan increase in the resistance of the current path in cooled regions and an increase in the Joule heating thereof.
By way of example, ferromagnetic material such as iron, nickel, and cobalt, and their alloys exhibit large changes in relative permeability as their temperature goes through a tran-sition point called the "Curie" point. For many iron-nickel alloys this Curie point occurs at about 450C., above which the ~ -relative permeability is near unity and below which it is high, perhaps 100 to 1000, for the magnetic field strengths that would be utilized in this application. An applied RF signal causes current to flow in the surface conductor of the blade near the ;
cutting edge which heats the edge to about 500C. prior to con-tact with tissues. When portions of the cutting edge are cooled upon contact with tissues, the cooled portions may drop in temperature below the Curie point and this will increase the relative permeability from near unity to above 100. mhe asso-ciated skin depth will decrease more than 10 to 1 and heating will increase proportionately in the cooled portion.
In accordance with the present invention, a scalpel blade of electrically insulating material such as alumina ~7'736~
ceramic is electrically heated in the region of the cutting edge thereof by conducting high frequency current along con~
ductors near the cutting edge, which conductors are formed of ferromagnetic material disposed on the insulating material of the blade.
Description of the Drawings Figure 1 is a side view of the surgical instrument according to the present invention; and Figure 2 is an end sectional view of the blade of the apparatus of Figure 1.
Description of the Preferred Embodiment _ _ Referring now to Figures 1 and 2 there is shown one embodiment of the present invention including a blade portion 9 of electrically insulating material such as alumina ceramic attached to a handle portion 11 to form the surgical instrument.
A signal conductor 13 of ferromagnetic material such as nickel-iron is disposed on the blade 9 adjacent the cutting edge 21 to form a complete conduction path along one side of the blade 9 and back along the other side of the blade. Input power at radio frequencies may be supplied to the conductor 13 from power source 19 through connection means 15 and 17.
With the current-carrying conductor 9 formed of ferromagnetic material, the skin depth characteristic pre-viously discussed can be utilized advantageously for temper-ature regulation. Current flowing through the ferromagnetic conductor 13 will flow on the inside of the conductor at the skin depth for the material and heat the ferromagnetic ma-terial and the ceramic cutting edge 21 thermally coupled thereto. From an operating temperature in air which is above the Curie temperature, portions of the cutting edge will cool -~; ,. :
1~'7736Ei as it touches tissue and its operating temperature may drop below the Curie temperature and the skin depth will decrease about 10 to 1 giving approximately a 10 to 1 local increase in heating. To achieve a 10 to 1 power increase, not only must the relative permeability increase 100 to 1 when cooled by tissue contact, but also the skin depth at pre-cutting operative con-ditions in air must be approximately two-thirds the thickness of the conductor or less in order to realize the 10 to 1 skin depth reduction. Thus, for a suitably thin scalpel blade with a suitably thin ferromagnetic self-regulating conductive heater disposed upon it, high frequencies may be required to establish the requisite skin depths. The following tabulation shows the frequency required for various skin depths above and below the Curie point in a 50:50 iron-nickel ferromagnetic alloy and shows the relative power dissipation o~ a 40 mil wide conductor dis-posed continuously upon both facets of a scalpel blade in the region of a 3 cm. cutting edge when energized by a current of about 3 amperes:
Temper- Permea- Skin ature Resistivity bility Frequency Depth Resistance Power C. ohms-cm(10 6) MHz mils ohms watts/cm (inch 3 of cutting x 10 _) edge 500 105 1 6 8.3 .29 .88 500 105 1 20 4.5 .54 1.61 500 105 1 100 2.0 1.20 3.Sl 400 100 100 6 0.81 2.87 8.62 400 100 100 20 0.44 5.25 15.7 28 400 100 100 100 0.20 11.7 35.2 _ :: : - ,. . . .
. ' ' ' ' ~
1(~'773f~
A layer of insulation 23 is disposed over the conductors 13 to insulate the tissue being cut from the electrical currents.
The high frequency signal source 19 may be adjustable in signal amplitude or in frequency, or both, to adjust the average operating temperature of the cutting edge. The fre-quency may be adjusted to alter the skin depth, as described above, and thereby to establish the ambient operating temperature 8 of the cutting edge in air.
..
Claims (7)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. A blade comprising:
a cutting means including a cutting edge;
electrical conductor means disposed near said cutting edge, said electrical conductor means including a material being capable of varying the skin depth of the conduction path for alternating electrical current therethrough; and a source of radio frequency electrical current, said source being connected to said electrical conductor means for supplying radio-frequency electrical current thereto.
a cutting means including a cutting edge;
electrical conductor means disposed near said cutting edge, said electrical conductor means including a material being capable of varying the skin depth of the conduction path for alternating electrical current therethrough; and a source of radio frequency electrical current, said source being connected to said electrical conductor means for supplying radio-frequency electrical current thereto.
2. A hemostatic surgical blade comprising:
a cutting means including a tissue-cutting edge capable of operating at an elevated temperature; and electrical conductor means disposed near said cutting edge, said electrical conductor means including a material being capable of varying the skin depth of the conduction path for alternating electrical current therethrough;
and a source of radio frequency electrical current, said source being connected to said electrical conductor means for supplying radio-frequency electrical current thereto.
a cutting means including a tissue-cutting edge capable of operating at an elevated temperature; and electrical conductor means disposed near said cutting edge, said electrical conductor means including a material being capable of varying the skin depth of the conduction path for alternating electrical current therethrough;
and a source of radio frequency electrical current, said source being connected to said electrical conductor means for supplying radio-frequency electrical current thereto.
3. A surgical blade as in claim 2 wherein said elec-trical conductor means includes a material having a permea-bility which varies inversely with temperature over a selected temperature range.
4. A surgical blade as in claim 2 wherein said material of said electrical conductor means exhibits a Curie point transition in permeability within the range of temperatures from about 300°C to about 1,000°C.
5. A surgical blade as in claim 2 wherein said material of said electrical conductor is a ferromagnetic material.
6. A surgical blade as in claim 2 wherein said material of the electrical conductor means includes an element selected from the group consisting of iron, nickel and cobalt.
7. A surgical blade as in claim 2 comprising a layer of insulated material disposed over said electrical conductor means to insulate tissue being cut from electrical shock.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US05/558,335 US4185632A (en) | 1970-08-13 | 1975-03-14 | Surgical instrument having self-regulated electrical skin-depth heating of its cutting edge and method of using the same |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1077366A true CA1077366A (en) | 1980-05-13 |
Family
ID=24229150
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA246,546A Expired CA1077366A (en) | 1975-03-14 | 1976-02-25 | Surgical instrument having self-regulated electrical skin-depth heating of its cutting edge and method of using the same |
Country Status (11)
| Country | Link |
|---|---|
| JP (1) | JPS51122987A (en) |
| AU (1) | AU500503B2 (en) |
| BR (1) | BR7601547A (en) |
| CA (1) | CA1077366A (en) |
| DE (1) | DE2609327C3 (en) |
| FR (1) | FR2303518A1 (en) |
| GB (1) | GB1546627A (en) |
| NL (1) | NL7602177A (en) |
| SE (1) | SE412842B (en) |
| SU (1) | SU720995A3 (en) |
| ZA (1) | ZA761133B (en) |
Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2022974A (en) * | 1978-04-20 | 1979-12-19 | Shaw R F | Improved electrically heated apparatus and method and material |
| WO1993021839A1 (en) * | 1992-05-01 | 1993-11-11 | Hemostatix Corporation | Surgical instruments having auto-regulating heater |
| WO2006033395A1 (en) | 2004-09-22 | 2006-03-30 | Olympus Corporation | Organic tissue sampling device |
| DE102006005224B4 (en) * | 2006-01-31 | 2008-09-04 | P + P Medical Gmbh | Device for separating an existing from an electrically conductive material Gelenkendoprothese of biological and / or biocompatible materials |
| US9730749B2 (en) * | 2009-04-17 | 2017-08-15 | Domain Surgical, Inc. | Surgical scalpel with inductively heated regions |
| US20180071011A1 (en) * | 2016-09-06 | 2018-03-15 | I.C. Medical, Inc. | Monopolar electrosurgery blade and electrosurgery blade assembly |
| US10792095B2 (en) * | 2017-03-05 | 2020-10-06 | I.C. Medical, Inc. | Monopolar electrosurgery pencil with argon beam capability |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3234356A (en) * | 1963-05-07 | 1966-02-08 | Raymond F Babb | Electrically heated medical implement |
| US3826263A (en) * | 1970-08-13 | 1974-07-30 | R Shaw | Electrically heated surgical cutting instrument |
| US3768482A (en) * | 1972-10-10 | 1973-10-30 | R Shaw | Surgical cutting instrument having electrically heated cutting edge |
-
1976
- 1976-02-25 CA CA246,546A patent/CA1077366A/en not_active Expired
- 1976-02-25 SE SE7602291A patent/SE412842B/en unknown
- 1976-02-25 ZA ZA761133A patent/ZA761133B/en unknown
- 1976-02-26 GB GB7698/76A patent/GB1546627A/en not_active Expired
- 1976-03-03 NL NL7602177A patent/NL7602177A/en not_active Application Discontinuation
- 1976-03-05 AU AU11717/76A patent/AU500503B2/en not_active Expired
- 1976-03-06 DE DE2609327A patent/DE2609327C3/en not_active Expired
- 1976-03-12 FR FR7607177A patent/FR2303518A1/en not_active Withdrawn
- 1976-03-12 SU SU762333504A patent/SU720995A3/en active
- 1976-03-12 JP JP51027027A patent/JPS51122987A/en active Granted
- 1976-03-12 BR BR7601547A patent/BR7601547A/en unknown
Also Published As
| Publication number | Publication date |
|---|---|
| DE2609327C3 (en) | 1979-07-05 |
| GB1546627A (en) | 1979-05-23 |
| JPS6128339B2 (en) | 1986-06-30 |
| BR7601547A (en) | 1976-09-14 |
| JPS51122987A (en) | 1976-10-27 |
| SE7602291L (en) | 1976-09-15 |
| SU720995A3 (en) | 1980-03-05 |
| SE412842B (en) | 1980-03-24 |
| NL7602177A (en) | 1976-09-16 |
| DE2609327B2 (en) | 1978-11-09 |
| AU500503B2 (en) | 1979-05-24 |
| ZA761133B (en) | 1977-02-23 |
| DE2609327A1 (en) | 1976-09-30 |
| AU1171776A (en) | 1977-09-08 |
| FR2303518A1 (en) | 1976-10-08 |
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