ELECTROSURGICAL BLADE ELECTRODE ADDING PRECISION DISSECTION PERFORMANCE AND TACTILE FEEDBACK

An electrosurgical blade (900) configured to couple to an RF electrosurgical instrument (100). The electrosurgical blade (900) includes a proximal portion (900a) configured to couple to a blade receptacle (104) of an RF electrosurgical instrument (100), a coagulation section (920) extending distally from the proximal portion (900a), a blade edge (940) defined around a periphery of the electrosurgical blade (900), and a ramped surface (930) extending between the coagulation section (920) and the blade edge (940). The blade edge (940) includes a right-angled tip (944) and is defined by a first side (941) extending longitudinally, a second side (942) extending longitudinally and having a curved portion (942c), and a distal side (943) extending laterally.

FIELD

The present disclosure relates to an electrosurgical electrode and, more particularly, to an electrosurgical blade electrode having an asymmetric configuration and insulative coating for precise dissection during an electrosurgical procedure.

BACKGROUND

Electrosurgical instruments have become widely used by surgeons in recent years. By and large, most electrosurgical instruments are hand-held instruments, e.g., an electrosurgical pencil, which transfer electrosurgical energy, e.g., radio-frequency (RF) electrosurgical energy, to a tissue site via an electrosurgical electrode. Typically, the electrosurgical energy is returned to the electrosurgical source via a return electrode pad positioned under a patient (i.e., a monopolar system configuration) or a smaller return electrode positionable in bodily contact with or immediately adjacent to the surgical site (i.e., a bipolar system configuration). The waveforms produced by the RF source yield a predetermined electrosurgical effect known generally as electrosurgical cutting and fulguration.

Typically, electrosurgical electrodes configured for electrosurgical use are subject to high temperatures at least where an electrosurgical arc emanates during the electrosurgical procedure, e.g., fulguration or coagulation. In some instances, the heat generated by the electrosurgical electrode during an electrosurgical procedure may cause proteins in bodily fluids and/or tissue to coagulate and adhere to the electrodes. To combat this adhering of bodily fluids and/or tissue to the electrosurgical electrodes, an insulative coating, e.g., a Teflon polymer, may be applied to the electrosurgical electrode.

Typical open electrode blades are symmetrical in design, are uniformly flat or have a slightly tapered cross section. These geometrical features enable the most common use for blade electrodes, blunt dissection and spot coagulation. However, the growing need for precision dissection capabilities and improved healing response (reduced thermal damage) on long skin incisions, has brought about a new family of blade electrodes that offer RF concentration features along the entire length of the blade. Two common features that enable precision dissection are either a sharp needle like electrode or a narrow cross section. Both designs have safety concerns in the operating rooms though. Specifically, the needle adds a sharp object that could perforate protective gloves and the RF sharp blades have no controlling feature to reduce the amount of the blade that can enter the dissection plane. When active, the blade can easily plunge into tissue with very little resistance (even less resistance than a surgical blade).

SUMMARY

The following aspects of electrosurgical instruments, and in particular, electrosurgical blade electrodes for electrosurgical instruments, incorporate features to enable fine precision dissection while still maintaining the coagulation capabilities of the blade electrodes. In particular, aspects of electrosurgical blade electrodes disclosed herein include structural features and properties that enable precision dissection of tissue, improving maneuverability of the blade electrode though tissue and improving safety by providing tactile features to the user or robotic system at set depths through tissue. Some aspects of electrosurgical blade electrode designs disclosed herein offer a significantly reduced section for precision on the edge of the blade, then two semi-circular cut outs that also provide the tactile feedback for detecting the depth of the electrode during tissue dissection. The reduced width of the cross section at this location improves the maneuverability of the blade and ultimately the instrument.

In an aspect, the present disclosure is directed to an electrosurgical blade configured to couple to an RF electrosurgical instrument. The electrosurgical blade includes a proximal portion configured to couple to a blade receptacle of an RF electrosurgical instrument, a first section extending distally from the proximal portion and having a first thickness, a second section extending distally from the first section and having a second thickness less than the first thickness thereby defining a first step between the first section and the second section, a third section extending distally from the second section and having a third thickness less than the second thickness thereby defining a second step between the second section and the third section, and a blade edge disposed along a peripheral edge of the third section.

The blade edge may be defined by a first side, a second side, and a third side, where the first side has a first length and the second side has a second length less than the first length.

In an aspect, the third section is configured to transmit a higher RF concentration than the second section to easily start a transection. Additionally or alternatively, the first section is coated to limit RF energy transmission from the first section relative to the remaining sections thereof. The second section may additionally or alternatively be coated to limit RF energy transmission from the second section.

In an aspect, at least one of the first section or the second section is configured to transmit RF energy therefrom only when provided a high voltage coagulation signal.

The second step is dimensioned and configured to provide a tactile feedback to a user during dissection. At least one of the first step or the second step may be a ramped surface or a non-ramped perpendicular surface.

In another aspect of the present disclosure, an RF electrosurgical instrument is provided. The RF electrosurgical instrument includes a blade receptacle and an electrosurgical blade operatively coupled thereto. The electrosurgical blade includes a proximal portion configured to couple to a blade receptacle of an RF electrosurgical instrument, a first section extending distally from the proximal portion and having a first thickness, a second section extending distally from the first section and having a second thickness less than the first thickness thereby defining a first step between the first section and the second section, a third section extending distally from the second section and having a third thickness less than the second thickness thereby defining a second step between the second section and the third section, and a blade edge disposed along a peripheral edge of the third section.

The blade edge may be defined by a first side, a second side, and a third side, where the first side has a first length and the second side has a second length less than the first length.

In an aspect, the third section is configured to transmit a higher RF concentration than the second section to easily start a transection. Additionally or alternatively, the first section is coated to limit RF energy transmission from the first section relative to the remaining sections thereof. The second section may additionally or alternatively be coated to limit RF energy transmission from the second section.

In an aspect, at least one of the first section or the second section is configured to transmit RF energy therefrom only when provided a high voltage coagulation signal.

The second step is dimensioned and configured to provide a tactile feedback to a user during dissection. At least one of the first step or the second step may be a ramped surface or a non-ramped perpendicular surface.

In yet another aspect of the present disclosure, an electrosurgical system is provided. The electrosurgical system includes an electrosurgical generator configured to generate RF electrosurgical energy and an RF electrosurgical instrument configured to couple to the electrosurgical generator and transmit RF electrosurgical energy to tissue. The RF electrosurgical instrument includes a blade receptacle and an electrosurgical blade operatively coupled thereto. The electrosurgical blade includes a proximal portion configured to couple to a blade receptacle of an RF electrosurgical instrument, a first section extending distally from the proximal portion and having a first thickness, a second section extending distally from the first section and having a second thickness less than the first thickness thereby defining a first step between the first section and the second section, a third section extending distally from the second section and having a third thickness less than the second thickness thereby defining a second step between the second section and the third section, and a blade edge disposed along a peripheral edge of the third section.

The blade edge may be defined by a first side, a second side, and a third side, where the first side has a first length and the second side has a second length less than the first length.

In an aspect, the third section is configured to transmit a higher RF concentration than the second section to easily start a transection. Additionally or alternatively, the first section is coated to limit RF energy transmission from the first section relative to the remaining sections thereof. The second section may additionally or alternatively be coated to limit RF energy transmission from the second section.

In an aspect, at least one of the first section or the second section is configured to transmit RF energy therefrom only when provided a high voltage coagulation signal.

The second step is dimensioned and configured to provide a tactile feedback to a user during dissection. At least one of the first step or the second step may be a ramped surface or a non-ramped perpendicular surface.

Traditional monopolar open blades utilize radiofrequency electrical energy to heat the tissue to achieve transection or hemostasis. The activation of RF power can cause inevitable sparking, which, although may assist in the hemostasis, can cause unintended thermal damage to the nearby tissue and critical structure and has a high risk of deflagration in the surgical environment. Especially in surgeries that are sensitive to thermal damage, surgeons have to be very careful when activating monopolar blades to prevent nerves and vessels from unintended damage. The disclosed blade configurations have less thermal spread and lower activation power to meet the needs of precise surgeries and lower the risk of potential damage to nearby tissue and critical structures. In particular, the present disclosure provides an asymmetric monopolar open blade with partial insulative coating for achieving minimal lateral thermal damage and smoke generation when activated to transect tissue. The disclosed blade includes a tip feature that enable surgeons to perform precise dissection and hemostasis while utilizing a lower power setting.

In accordance with another aspect, the present disclosure is directed to an electrosurgical blade configured to couple to an RF electrosurgical instrument. The electrosurgical blade includes a proximal portion configured to couple to a blade receptacle of an RF electrosurgical instrument, a coagulation section extending distally from the proximal portion, a blade edge defined around a periphery of the electrosurgical blade, and a ramped surface extending between the coagulation section and the blade edge. The blade edge includes a right-angled tip and is defined by a first side extending longitudinally, a second side extending longitudinally and having a curved portion, and a distal side extending laterally.

In an aspect, the right-angled tip of the blade edge is defined at a point where the first side and the distal side meet.

In an aspect, the right-angled tip of the blade edge is configured to transmit a higher RF concentration than the coagulation section to easily start a transection.

In an aspect, an insulative guard is disposed around at least a portion of the proximal portion.

In an aspect, a coating is disposed around at least an exterior surface of the coagulation section or an exterior surface of the ramped surface. A thickness of the coating disposed around the exterior surface of the coagulation section may be non-uniform or uniform. Additionally or alternatively, a thickness of the coating disposed around the exterior surface of the ramped surface is non-uniform.

In another aspect of the present disclosure, an RF electrosurgical instrument is provided. The RF electrosurgical instrument includes a blade receptacle and an electrosurgical blade operatively coupled thereto. The electrosurgical blade includes a proximal portion configured to couple to a blade receptacle of an RF electrosurgical instrument, a coagulation section extending distally from the proximal portion, a blade edge defined around a periphery of the electrosurgical blade, and a ramped surface extending between the coagulation section and the blade edge. The blade edge includes a right-angled tip and is defined by a first side extending longitudinally, a second side extending longitudinally and having a curved portion, and a distal side extending laterally.

In an aspect, the right-angled tip of the blade edge is defined at a point where the first side and the distal side meet.

In an aspect, the right-angled tip of the blade edge is configured to transmit a higher RF concentration than the coagulation section to easily start a transection.

In an aspect, an insulative guard is disposed around at least a portion of the proximal portion.

In an aspect, a coating is disposed around at least an exterior surface of the coagulation section or an exterior surface of the ramped surface. A thickness of the coating disposed around the exterior surface of the coagulation section may be non-uniform or uniform. Additionally or alternatively, a thickness of the coating disposed around the exterior surface of the ramped surface is non-uniform.

In yet another aspect of the present disclosure, an electrosurgical system is provided. The electrosurgical system includes an electrosurgical generator configured to generate RF electrosurgical energy and an RF electrosurgical instrument configured to couple to the electrosurgical generator and transmit RF electrosurgical energy to tissue. The RF electrosurgical instrument includes a blade receptacle and an electrosurgical blade operatively coupled thereto. The electrosurgical blade includes a proximal portion configured to couple to a blade receptacle of an RF electrosurgical instrument, a coagulation section extending distally from the proximal portion, a blade edge defined around a periphery of the electrosurgical blade, and a ramped surface extending between the coagulation section and the blade edge. The blade edge includes a right-angled tip and is defined by a first side extending longitudinally, a second side extending longitudinally and having a curved portion, and a distal side extending laterally.

In an aspect, the right-angled tip of the blade edge is defined at a point where the first side and the distal side meet.

In an aspect, the right-angled tip of the blade edge is configured to transmit a higher RF concentration than the coagulation section to easily start a transection.

In an aspect, an insulative guard is disposed around at least a portion of the proximal portion.

In an aspect, a coating is disposed around at least an exterior surface of the coagulation section or an exterior surface of the ramped surface. A thickness of the coating disposed around the exterior surface of the coagulation section may be non-uniform or uniform. Additionally or alternatively, a thickness of the coating disposed around the exterior surface of the ramped surface is non-uniform.

DETAILED DESCRIPTION

Particular embodiments of the presently disclosed electrosurgical blade electrodes are described in detail with reference to the figures wherein like reference numerals identify similar or identical elements. As used herein, the term “distal” refers to that portion which is further from the user while the term “proximal” refers to that portion which is closer to the user or surgeon.

The following aspects of electrosurgical instruments, and in particular, electrosurgical blade electrodes for electrosurgical instruments, incorporate features to enable fine precision dissection while still maintaining the coagulation capabilities of the blade electrodes. In particular, aspects of electrosurgical blade electrodes disclosed herein include structural features and properties that enable precision dissection of tissue, improving maneuverability of the electrode though tissue and improving safety, for example, by providing tactile features to the user or robotic system at set depths through tissue, by incorporating coatings, and/or by having specific configurations and dimensions that demand lower radiofrequency power settings. Some aspects of electrosurgical blade electrode designs disclosed herein offer a significantly reduced section for precision on the edge of the blade, then two semi-circular cut outs that also provide the tactile feedback for detecting the depth the blade electrode during tissue dissection. The reduced width of the cross section at this location improves the maneuverability of the blade and ultimately the instrument.

Although the following disclosure describes the electrosurgical blade electrodes as being used with a handheld pencil-type electrosurgical instrument, it is understood that the benefits of the structural features of all of the aspects of the electrosurgical blade electrodes disclosed herein may be realized by robotic surgical systems, and the following disclosure is not intended to be limiting.

FIG. 1sets forth a side, perspective view of an electrosurgical system including an RF electrosurgical generator “G” and RF electrosurgical instrument100configured to couple to the RF electrosurgical generator “G” via a plug assembly200. The RF electrosurgical generator “G” generates RF electrosurgical energy which is configured to be transmitted to tissue via RF electrosurgical instrument100. To this end, RF electrosurgical instrument100includes an electrosurgical blade electrode10constructed in accordance with the aspects of the present disclosure.

As illustrated inFIG. 1, RF electrosurgical instrument100includes an elongated housing102having a top-half shell portion102aand a bottom-half shell portion102b.RF electrosurgical instrument100includes a blade receptacle104disposed at a distal end of housing102configured to operatively and removably connect to a replaceable electrosurgical blade electrode10. RF electrosurgical instrument100includes one or more activation switches (three activation switches120a-120care shown). Each activation switch120a-120ccontrols the transmission of RF electrical energy supplied from RF electrosurgical generator “G” to electrosurgical blade electrode10at different power levels or signals. For example, activation of activation switch120cmay be configured to provide a high voltage coagulation signal.

For a more detailed description of the RF electrosurgical instrument100including operative components associated therewith, reference is made to commonly-owned U.S. Pat. No. 7,879,033, entitled “Electrosurgical Pencil with Advanced ES Controls,” the entire contents of which are incorporated by reference herein.

With reference now toFIGS. 2A-2Celectrosurgical blade electrode10will be described in detail as electrosurgical blade200. Electrosurgical blade200may be fabricated from a conductive type material, such as, for example, stainless steel, or may be coated entirely or on selective portions thereof with an electrically conductive material.

Electrosurgical blade200may include a layer of insulative coating that may be applied evenly over the entire surface of electrosurgical blade200. Conversely, insulative coating may be applied in a non-even fashion. More particularly, electrosurgical blade200may include portions (e.g., areas that are intended to emanate electrosurgical energy to a tissue site) that have less insulative coating than other areas of the electrosurgical blade200(e.g., areas that are not intended to emanate electrosurgical energy to a tissue site or are intended to emanate a lower level of electrosurgical energy to a tissue site). The insulative coating may be made from any suitable material including but not limited to Teflon® coatings, Teflon® polymers, silicone and the like.

As noted above, electrosurgical blade200operatively and removably connects to blade receptacle104of RF electrosurgical instrument100(FIG. 1). To this end, a proximal portion200aof electrosurgical blade200is selectively retained by receptacle104within the distal end of housing102. Electrosurgical blade200extends distally beyond receptacle104and transmits RF electrosurgical energy to tissue during use.

Electrosurgical blade200includes a first section210, a second section220extending distally from the first section210, a third section230extending distally from the second section220, and a blade edge240disposed along a peripheral edge of the third section230. First section210of electrosurgical blade200has a first thickness T1and second section220of electrosurgical blade200has a second thickness T2which is less than the first thickness T1of first section210. The greater thickness T1of first section210, relative to the lesser thickness T2of second section220, provides the function of limiting the amount of RF electrosurgical energy emitted to tissue from the first section210relative to the amount of RF electrosurgical energy emitted to tissue from the second section220, when the RF electrosurgical energy is transmitted to the electrosurgical blade200.

Additionally, the difference between the thickness T1of first section210and thickness T2of second section220defines a first step215between first section210and second section220of electrosurgical blade200. First step215may be a ramped surface defined between the surface of first section210and the surface of second section220. Alternatively, first step215may be a non-ramped surface, that is, a surface disposed perpendicular to the parallel planes of the surface of the first section210and the surface of the second section220. Additionally, first step215may define an axis that is entirely perpendicular to a longitudinal axis defined by electrosurgical blade200(shown inFIG. 2B), or alternatively, may define an axis that is not substantially perpendicular to the longitudinal axis of electrosurgical blade200(not shown).

First step215provides the user with tactile feedback as electrosurgical blade200is penetrating deeper through tissue. In particular, after electrosurgical blade200is initially penetrated through tissue, the further penetration through the tissue (e.g., after the first few millimeters of tissue) is alerted to the user via the tactile feedback caused by the tissue abutting against first step215. In hand-held surgical applications, the user will feel the tactile feedback enabled by first step215as the user penetrates further through the tissue and tissue abuts first step215. In robotic surgical applications, the tactile feedback caused by tissue pressing against first step215generates a peak in resistance measured by sensors which can be used to determine that tissue is abutting first step215or that first step215has passed through tissue.

Third section230of electrosurgical blade200has a third thickness T3which is less than the second thickness T2of second section220. The greater thickness T2of second section220, relative to the lesser thickness T3of third section230, provides the function of limiting the amount of RF electrosurgical energy emitted to tissue from the second section220relative to the amount of RF electrosurgical energy emitted to tissue from the third section230, when the RF electrosurgical energy is transmitted to the electrosurgical blade200.

Additionally, the difference between the thickness T3of third section230and thickness T2of second section220defines a second step225between third section230and second section220of electrosurgical blade200. Second step225may be a ramped surface defined between the surface of third section230and the surface of second section220. Alternatively, second step225may be a non-ramped surface, that is, a surface disposed perpendicular to the parallel planes of the surface of the third section230and the surface of the second section220. Additionally, second step225may define an axis that is entirely perpendicular to a longitudinal axis defined by electrosurgical blade200(not shown), may define an axis that is partially perpendicular to the longitudinal axis of electrosurgical blade200(not shown), or alternatively, may define a particular shape, for example, the “U” shape shown inFIG. 2B.

Second step225provides the user with tactile feedback as electrosurgical blade200is penetrating deeper through tissue. In particular, after blade edge240of electrosurgical blade200is initially penetrated through tissue to create an incision, the further penetration through the tissue (e.g., immediately following the penetration of tissue) is alerted to the user via the tactile feedback caused by the tissue abutting second step225. In hand-held surgical applications, the user will feel the tactile feedback enabled by second step225immediately following the initial incision through tissue and tissue abuts second step225. In robotic surgical applications, the tactile feedback caused by tissue against second step225generates a peak in resistance measured by sensors which can be used to determine that tissue is abutting second step225or that second step225has passed through tissue.

Third section230of electrosurgical blade200includes a blade edge240disposed at a distal portion thereof. Blade edge240is defined by a first side242, second side244, and third side246. In an aspect, the length of first side242is greater than the length of third side246. Additionally, or alternatively, any or all of first side242, second side244, or third side246may be a blunt edge or a sharpened edge.

Although the structural features of first section210, second section220, and third section230of electrosurgical blade200are illustrated and described from the perspective of the topside of electrosurgical blade200, it is understood that some or all of the features may also be present on the bottomside of electrosurgical blade200. Thus, the bottomside of electrosurgical blade200may be a planar surface along its length or may include some or all of the features present on the topside thereof.

Turning now toFIG. 3, another electrosurgical blade electrode10will be described in detail as electrosurgical blade300. Electrosurgical blade300may be fabricated from a conductive type material, such as, for example, stainless steel, or may be coated entirely or on selective portions thereof with an electrically conductive material.

Electrosurgical blade300may include a layer of insulative coating that may be applied evenly over the entire surface of electrosurgical blade300. Conversely, the insulative coating may be applied in a non-even fashion. More particularly, electrosurgical blade300may include portions (e.g., areas that are intended to emanate electrosurgical energy to a tissue site) that have less insulative coating than other areas of the electrosurgical blade300(e.g., areas that are not intended to emanate electrosurgical energy to a tissue site or are intended to emanate a lower level of electrosurgical energy to a tissue site). The insulative coating may be made from any suitable material including but not limited to Teflon coatings, Teflon polymers, silicone and the like.

As noted above, electrosurgical blade300operatively and removably connects to blade receptacle104of RF electrosurgical instrument100(FIG. 1). To this end, a proximal portion (not shown) of electrosurgical blade300is selectively retained by receptacle104within the distal end of housing102. Electrosurgical blade300extends distally beyond receptacle104and transmits RF electrosurgical energy to tissue during use.

Electrosurgical blade300includes a first section (not shown), a second section320extending distally from the first section, a third section330extending distally from the second section320, and a blade edge340disposed along a peripheral edge of the third section330. Although not explicitly shown, like electrosurgical blade200, first section of electrosurgical blade300has a first thickness (not shown) and second section320of electrosurgical blade300has a second thickness320T which is less than the first thickness of first section. The greater thickness of the first section, relative to the lesser thickness320T of second section320, provides the function of limiting the amount of RF electrosurgical energy emitted to tissue from the first section relative to the amount of RF electrosurgical energy emitted to tissue from the second section320, when the RF electrosurgical energy is transmitted to the electrosurgical blade300.

Additionally, the difference between the thickness of the first section and thickness320T of second section320defines a first step (not shown) between the first section and second section320of electrosurgical blade300. First step (not shown) may be a ramped surface defined between the surface of the first section and the surface of second section320. Alternatively, first step may be a non-ramped surface, that is, a surface disposed perpendicular to the parallel planes of the surface of the first section and the surface of the second section320.

First step provides the user with tactile feedback as electrosurgical blade300is penetrating deeper through tissue. In particular, after electrosurgical blade300is initially penetrated through tissue, the further penetration through the tissue (e.g., after the first few millimeters of tissue) is alerted to the user via the tactile feedback caused by the tissue abutting against first step. In hand-held surgical applications, the user will feel the tactile feedback enabled by first step as the user penetrates further through the tissue and tissue abuts first step. In robotic surgical applications, the tactile feedback caused by tissue against first step generates a peak in resistance measured by sensors which can be used to determine that tissue is abutting first step or that first step has passed through tissue.

Third section330of electrosurgical blade300has a third thickness330T which is less than the second thickness320T of second section320. The greater thickness320T of second section320, relative to the lesser thickness330T of third section330, provides the function of limiting the amount of RF electrosurgical energy emitted to tissue from the second section320relative to the amount of RF electrosurgical energy emitted to tissue from the third section330, when the RF electrosurgical energy is transmitted to the electrosurgical blade300.

Additionally, the difference between the thickness330T of third section330and thickness320T of second section320defines a second step325between third section330and second section320of electrosurgical blade300. Second step325may be a ramped surface defined between the surface of third section330and the surface of second section320. Alternatively, second step325may be a non-ramped surface, that is, a surface disposed perpendicular to the parallel planes of the surface of the third section330and the surface of the second section320. Additionally, second step325may define an axis that is entirely perpendicular to a longitudinal axis defined by electrosurgical blade300(not shown), may define an axis that is partially perpendicular to the longitudinal axis of electrosurgical blade300(not shown), or alternatively, may define a particular shape, for example, the “U” shape shown inFIG. 3.

Second step325provides the user with tactile feedback as electrosurgical blade300is penetrating deeper through tissue. In particular, after blade edge340of electrosurgical blade300is initially penetrated through tissue to create an incision, the further penetration through the tissue (e.g., immediately following the penetration of tissue) is alerted to the user via the tactile feedback caused by the tissue abutting second step325. In hand-held surgical applications, the user will feel the tactile feedback enabled by second step325immediately following the initial incision through tissue and tissue abuts second step325. In robotic surgical applications, the tactile feedback caused by tissue against second step325generates a peak in resistance measured by sensors which can be used to determine that tissue is abutting second step325or that second step325has passed through tissue.

Third section330of electrosurgical blade300includes a blade edge340disposed at a distal portion thereof. Blade edge340is defined by a first side342, second side344, and third side346. In an aspect, the length of first side342is equal the length of third side346. Additionally, either or both of first side342or third side346may be curved or otherwise arcuate from its proximal end to its distal end as illustrated inFIG. 3. Additionally, or alternatively, any or all of first side342, second side344, or third side346may be a blunt edge or a sharpened edge.

Although the structural features of second section320and third section330of electrosurgical blade300are illustrated and described from the perspective of the topside of electrosurgical blade300, it is understood that some or all of the features may also be present on the bottomside of electrosurgical blade300. Thus, the bottomside of electrosurgical blade300may be a planar surface along its length or may include some or all of the features present on the topside thereof.

Turning now toFIG. 4, another electrosurgical blade electrode10will be described in detail as electrosurgical blade400. Electrosurgical blade400is similar to electrosurgical blade300and thus only the differences between the two, generally, will be described. Electrosurgical blade400includes a second section420which steps down to third section430via second step425. Like second step325of electrosurgical blade300, second step425of electrosurgical blade400may be “U” shaped as shown inFIG. 4.

Third section430of electrosurgical blade400includes a blade edge440. Blade edge440includes a first side442, second side444, and third side446. Respective proximal portions of first side442and third side446are contiguous with the sides of second section420. Mid portions of first side442and third side446taper inward toward a longitudinal axis defined by electrosurgical blade400to meet at second side444. Second side444may be rounded as shown inFIG. 4, or alternatively, may be a single point in which first side442and third side446meet thereby defining a pointed tip.

Although the structural features of second section420and third section430of electrosurgical blade400are illustrated and described from the perspective of the topside of electrosurgical blade400, it is understood that some or all of the features may also be present on the bottomside of electrosurgical blade400. Thus, the bottomside of electrosurgical blade400may be a planar surface along its length or may include some or all of the features present on the topside thereof.

Turning now toFIG. 5, another electrosurgical blade electrode10will be described in detail as electrosurgical blade500. Electrosurgical blade500may be fabricated from a conductive type material, such as, for example, stainless steel, or may be coated entirely or on selective portions thereof with an electrically conductive material.

As described in greater detail below, electrosurgical blade500offers a significantly reduced section for precision on the edge of the blade, then two semi-circular cut outs that also provides the tactile feedback for detecting the depth of the electrosurgical blade500during tissue dissection. The reduced width of the cross section at this location improves the maneuverability when positioned through tissue and for moving along tissue.

Electrosurgical blade500may include a layer of insulative coating that may be applied evenly over the entire surface of electrosurgical blade500. Conversely, insulative coating may be applied in a non-even fashion. More particularly, electrosurgical blade500may include portions (e.g., areas that are intended to emanate electrosurgical energy to a tissue site) that have less insulative coating than other areas of the electrosurgical blade500(e.g., areas that are not intended to emanate electrosurgical energy to a tissue site or are intended to emanate a lower level of electrosurgical energy to a tissue site). The insulative coating may be made from any suitable material including but not limited to Teflon® coatings, Teflon® polymers, silicone and the like.

As noted above, electrosurgical blade500operatively and removably connects to blade receptacle104of RF electrosurgical instrument100(FIG. 1). To this end, a proximal portion (not shown) of electrosurgical blade500is selectively retained by receptacle104within the distal end of housing102. Electrosurgical blade500extends distally beyond receptacle104and transmits RF electrosurgical energy to tissue during use.

Electrosurgical blade500includes a first section (not shown), a second section520extending distally from the first section, a third section530extending distally from the second section520, and a blade edge540disposed along a peripheral edge of the third section530. Although not explicitly shown, like electrosurgical blade200, first section of electrosurgical blade500has a first thickness (not shown) and second section520of electrosurgical blade500has a second thickness520T which is less than the first thickness of first section. The greater thickness of the first section, relative to the lesser thickness520T of second section520, provides the function of limiting the amount of RF electrosurgical energy emitted to tissue from the first section relative to the amount of RF electrosurgical energy emitted to tissue from the second section520, when the RF electrosurgical energy is transmitted to the electrosurgical blade500.

Additionally, the difference between the thickness of the first section and thickness520T of second section520defines a first step (not shown) between the first section and second section520of electrosurgical blade500. First step (not shown) may be a ramped surface defined between the surface of the first section and the surface of second section520. Alternatively, first step may be a non-ramped surface, that is, a surface disposed perpendicular to the parallel planes of the surface of the first section and the surface of the second section520.

First step provides the user with tactile feedback as electrosurgical blade500is penetrating deeper through tissue. In particular, after electrosurgical blade500is initially penetrated through tissue, the further penetration through the tissue (e.g., after the first few millimeters of tissue) is alerted to the user via the tactile feedback caused by the tissue abutting against first step. In hand-held surgical applications, the user will feel the tactile feedback enabled by first step as the user penetrates further through the tissue and tissue abuts first step. In robotic surgical applications, the tactile feedback caused by tissue against first step generates a peak in resistance measured by sensors which can be used to determine that tissue is abutting first step or that first step has passed through tissue.

Third section530of electrosurgical blade500is composed of a midsection532and a first side section534on one side of midsection532and a second side section536on the other side of midsection532. Midsection532extends the length of third section530. In an aspect, the surface of midsection532is coplanar with the surface of second section520. First side section534extends outward from one side of midsection532forming a ramped surface therefrom and defining a left second step525abetween it and second section520. Similarly, second side section536extends outward from the other side of midsection532forming another ramped surface therefrom and defining a right second step525bbetween it and second section520.

Third section530also includes a blade edge540defined about its periphery. Blade edge540is defined by first side542, second side544, and third side546. As shown inFIG. 5, second side544may be blunt and first side542and third side546may be equal in length. Additionally, at least one of first side542or third side546of blade edge540(and/or first side section534or second side section536) may have semi-circular cutouts542u,546udisposed along a length thereof. Semi-circular cutouts542u,546ucreate a region along third section530with a narrower width relative to the remaining portions of third section530. This narrower width provides the tactile feedback for detecting the depth the electrosurgical blade500during tissue dissection and improves its maneuverability.

Although the structural features of second section520and third section530of electrosurgical blade500are illustrated and described from the perspective of the topside of electrosurgical blade500, it is understood that some or all of the features may also be present on the bottomside of electrosurgical blade500. Thus, the bottomside of electrosurgical blade500may be a planar surface along its length or may include some or all of the features present on the topside thereof.

Each of first side section534and second side section536of third section530has a third thickness530T which is less than the second thickness520T of second section520. Midsection532of third section530has a substantially similar thickness to that of second section520. The greater thickness520T of second section520, relative to the lesser thickness530T of the sides of third section530, provides the function of limiting the amount of RF electrosurgical energy emitted to tissue from the second section520relative to the amount of RF electrosurgical energy emitted to tissue from the sides of third section530, when the RF electrosurgical energy is transmitted to the electrosurgical blade500.

Additionally, the difference between the thickness530T of the sides of third section530and thickness520T of second section520defines respective steps525a,525bbetween third section530and second section520of electrosurgical blade500. One or both of steps525a,525bmay be a ramped surface defined between the side surface of third section530and the surface of second section320. Alternatively, second step525may be a non-ramped surface, that is, a surface disposed perpendicular to the parallel planes of the side surface of the third section530and the surface of the second section520. Additionally, one or both of steps525a,525bmay define an axis that is entirely perpendicular to a longitudinal axis defined by electrosurgical blade500(shown inFIG. 5), may define an axis that is partially perpendicular to the longitudinal axis of electrosurgical blade500(not shown), or alternatively, may define a particular shape.

Steps525a,525bprovide the user with tactile feedback as electrosurgical blade500is penetrating deeper through tissue. In particular, after blade edge540of electrosurgical blade500is initially penetrated through tissue to create an incision, the further penetration through the tissue (e.g., immediately following the penetration of tissue) is alerted to the user via the tactile feedback caused by the tissue abutting either one of steps525a,525b.In hand-held surgical applications, the user will feel the tactile feedback enabled by either one of steps525a,525bimmediately following the initial incision through tissue and tissue abuts either one of steps525a,525b.In robotic surgical applications, the tactile feedback caused by tissue against either one of steps525a,525bgenerates a peak in resistance measured by sensors which can be used to determine that tissue is abutting either one of steps525a,525bor that either one of steps525a,525bhas passed through tissue.

Turning now toFIG. 6, another electrosurgical blade electrode10will be described in detail as electrosurgical blade600. Electrosurgical blade600may be fabricated from a conductive type material, such as, for example, stainless steel, or may be coated entirely or on selective portions thereof with an electrically conductive material. Electrosurgical blade600is similar to the other electrosurgical blades described herein and therefore only the differences therefrom will be described.

Electrosurgical blade600includes a second section620and a third section630extending distally from the second section620. A blade edge640is defined about the periphery of third section630. Additionally, third section630includes a “U” shaped midsection, a distal portion of which ramps down to blade edge640. Like electrosurgical blade500, electrosurgical blade600includes steps625a,625bon each side thereof. First side642of blade edge640and third side646of blade edge640are substantially equal in length and extend distally, tapering inward to meet at second side644.

Although the structural features of second section620and third section630of electrosurgical blade600are illustrated and described from the perspective of the topside of electrosurgical blade600, it is understood that some or all of the features may also be present on the bottomside of electrosurgical blade600. Thus, the bottomside of electrosurgical blade600may be a planar surface along its length or may include some or all of the features present on the topside thereof.

Turning now toFIGS. 7A-7B, another electrosurgical blade electrode10will be described in detail as electrosurgical blade700. Electrosurgical blade700may be fabricated from a conductive type material, such as, for example, stainless steel, or may be coated entirely or on selective portions thereof with an electrically conductive material. Electrosurgical blade700is similar to the other electrosurgical blades described herein and therefore only the differences therefrom will be described.

Electrosurgical blade700includes a second section720and a third section730extending distally from the second section720. In an aspect, the second section720is designed for coagulating tissue and the third section730is designed for cutting tissue. Thus, in one aspect, the area of the surface intended to contact tissue of the second section720is maximized, while the area of the surface intended to contact tissue in the third section730is minimized. A blade edge740is defined about the periphery of third section730. Additionally, at least a portion of third section630defines a concave profile shown as a shallow elliptical pocket750. The design of the shallow elliptical pocket750improves performance of electrosurgical blade700by reducing surface contact of electrosurgical blade700with tissue in portions that are not desired to contact tissue. Electrosurgical blade700optimizes the surface in contact with tissue immediately adjacent to blade edge740. As the tissue is divided by blade edge740, the other surfaces of electrosurgical blade700(e.g., shallow elliptical pocket750) are designed to not electrically or physically be in contact with the tissue, thereby minimizing the amount of RF energy that can transfer causing thermal spread and tissue sticking.

As shown inFIG. 7B, an elliptical pocket750is defined so that the blade edge740divides the tissue and the concave void defined by elliptical pockets750prevent tissue from contacting the surface (e.g., surface of third section730) of electrosurgical blade700. This configuration further minimizes the amount of thermal damage to the tissue, but still allows for hemostasis when the electrosurgical blade700is used on its coagulation surfaces (e.g., surfaces defined by second section720) and to some extent along the elliptical pocket750in coagulation mode. This feature also enables improved coating performance by not dragging (or minimizing the contact area of) the hot surfaces of the electrosurgical blade700through the tissue.

Although the structural features of second section720and third section730of electrosurgical blade700are illustrated and described from the perspective of the topside of electrosurgical blade700, it is understood that some or all of the features may also be present on the bottomside of electrosurgical blade700. Thus, the bottomside of electrosurgical blade700may be a planar surface along its length or may include some or all of the features present on the topside thereof.

Turning now toFIGS. 8A-8B, another electrosurgical blade electrode10will be described in detail as electrosurgical blade800. Electrosurgical blade800may be fabricated from a conductive type material, such as, for example, stainless steel, or may be coated entirely or on selective portions thereof with an electrically conductive material. Electrosurgical blade800is similar to the other electrosurgical blades described herein and therefore only the differences therefrom will be described.

Electrosurgical blade800includes a second section820and a third section830extending distally from the second section820. In an aspect, the second section820is designed for coagulating tissue and the third section830is designed for cutting tissue. Thus, in one aspect, the area of the surface intended to contact tissue of the second section820is maximized, while the area of the surface intended to contact tissue in the third section830is minimized. A blade edge840is defined about the periphery of third section830. Additionally, at least a portion of third section830defines a surface850that is minimized in width. The design of the surface850having a minimized width improves performance of electrosurgical blade800by reducing surface contact of electrosurgical blade800with tissue in portions that are not desired to contact tissue. Electrosurgical blade800optimizes the surface in contact with tissue immediately adjacent to blade edge840. As the tissue is divided by blade edge840, the other surfaces of electrosurgical blade800(e.g., surface850) are designed to minimize the area in which these surfaces contact tissue, thereby minimizing the amount of RF energy that can transfer causing thermal spread and tissue sticking. This feature also enables improved coating performance by not dragging (or minimizing the contact area of) the hot surfaces of the electrosurgical blade800through the tissue.

Although the structural features of second section820and third section830of electrosurgical blade800are illustrated and described from the perspective of the topside of electrosurgical blade800, it is understood that some or all of the features may also be present on the bottomside of electrosurgical blade800. Thus, the bottomside of electrosurgical blade800may be a planar surface along its length or may include some or all of the features present on the topside thereof.

Turning now toFIGS. 9A-9D, another electrosurgical blade electrode10will be described in detail as electrosurgical blade900. Electrosurgical blade900may be fabricated from a conductive material, such as, for example, stainless steel, or may be coated entirely or on selective portions thereof with an electrically conductive material. Electrosurgical blade900is similar to the above-described electrosurgical blades and therefore only the differences are described below.

Electrosurgical blade900extends from an insulative guard910, or alternatively, the insulative guard910is disposed around a proximal portion900aof the electrosurgical blade900. The insulative guard910prevents the electrosurgical blade900from cutting too deep into tissue which may cause unintended damage to the tissue layers or organs below the surface tissue. A distal portion900bof electrosurgical blade900includes a broad coagulation section920, extending distally from the proximal portion900a,and a blade edge940. The coagulation section920is designed for coagulating tissue and the blade edge940is defined around a perimeter of the electrosurgical blade900(e.g., around a perimeter of ramped surfaces930extending outwardly from the coagulation section920) and is designed for cutting tissue. Thus, in one aspect, the area of the surface intended to contact tissue of the coagulation section920is maximized.

Electrosurgical blade900is asymmetric (e.g., not identical on both sides of its centerline). In particular, as shown inFIGS. 9A-9B, blade edge940of electrosurgical blade900includes a first side941, a second side942, and a distal side943. The first side941is linear and extends longitudinally along a length of one side of the electrosurgical blade900to the distal side943, which is also linear and extends laterally and perpendicular to the first side941, where a right-angled tip944is formed at a point in which a distal end of the first side941and the distal side943meet. The second side942includes a linear portion9421and a curved portion942cand extends along a length of a second side of the electrosurgical blade900where the curved portion942cmeets the distal side943. A ramped surface930extends from the coagulation section920to the blade edge940.

The right-angled tip944is designed to form a current concentration and enables a surgeon to perform delicate operations on tissue, e.g. precise transection and spot coagulation, while also enabling the surgeon to perform operations at a significantly lower power setting (e.g., 5 W-20 W) due to the current concentration formed at the right-angled tip944. The curved portion942cof blade edge940is designed to leverage the use-habit of traditional cold scalpels which provides the surgeon the ability to perform superficial straight dissection.

With reference toFIG. 9C, the electrosurgical blade900may have a center thickness 900T ranging between 0.3 mm-0.8 mm, which provides sufficient rigidity to withstand bending forces during operation while also providing sufficient elasticity for a surgeon to intentionally bend the electrosurgical blade900when necessary or desired. The upper and lower ramped surfaces930extending from the first side941define a wedge angle941aand the upper and lower ramped surfaces930extending from second side942define a wedge angle942a,which may be the same as, or different from, wedge angle941a.In an aspect, either or both of wedge angle941aand wedge angle942ais within the range of 20 degrees to 40 degrees which contributes to the current concentration along first side941and second side942to enable smooth dissection using first side941or second side942with a lower power setting.

Turning now toFIG. 9D, coating990may be disposed around the external surface of electrosurgical blade900, for example, around at least a portion of the external surface of coagulation section920, ramped surfaces930, or blade edge940. Coating990may be an insulative coating, formed of a material having a high impedance in RF and which provides anti-stick performance in high temperatures (e.g., 300 degrees C.). Coating990may be formed of at least one of polymers (e.g., PTFE, PFA, etc.) and/or ceramics (e.g., TiN, CrN, Al2O3, etc.). The thickness of coating900varies from edge to edge, that is, from first side941to second side942. For example, the thickness of coating990may be greater at a center area (e.g., around coagulation section920) and lower closer to the edges of the electrosurgical blade900(e.g., around ramped surface930or blade edge940). In one aspect, the coating990has a thickness992on top of the coagulation section920, which is substantially uniform, and has a thickness993on top of the ramped surfaces930, which is not substantially uniform as the coating990approaches the edges (e.g., first side941and second side942). The thicknesses (e.g., thickness992and thickness993) of the coating990regulates the current to concentrate on the blade edge940and restricts sparking along the blade edge940thereby minimizing lateral thermal damage and surgical smoke generation.

Although the structural features of coagulation section920, ramped surface930, and blade edge940of electrosurgical blade900are illustrated and described from the perspective of the topside of electrosurgical blade900, it is understood that some or all of the features may also be present on the bottomside of electrosurgical blade900. Thus, the bottomside of electrosurgical blade900may be a planar surface along its length or may include some or all of the features present on the topside thereof.

Any of the above-described aspects of electrosurgical blade electrodes and blades may be coated entirely or on selective portions thereof with an electrically conductive and/or non-conductive material. In certain applications, the convex/concave nature of the blade enables the use of two different coating methods. For example, in certain aspects, for concave blade geometry, a more conductive non-stick coating can be used without impacting thermal spread. Also, for example, for convex blade cross sections, a less conductive non-stick coating may be used to limit the transmission of RF energy or other electrosurgical energy into the tissue.

Any or all portions of any of the electrosurgical blade electrodes disclosed herein may be formed by any suitable techniques, e.g., machining techniques and/or metal injection molding techniques. For example, any cutouts, edging, ramping, or other surface geometry may be formed by known milling techniques, etching techniques, or other techniques not specifically described.

From the foregoing and with reference to the various figures, those skilled in the art will appreciate that certain modifications can also be made to the present disclosure without departing from the scope of the same. For example, electrosurgical blade electrode10may include other geometrical configurations.