Abstract: The disclosed technology is directed to a RF power generator and feedback control system used to regulate the electrical power delivered to a cutting filament (i.e., a cutting electrode) of an electrosurgical instrument. The electrosurgical instrument uses the delivered energy to form a cutting arc for ablating a tissue mass to access a target tissue therein. The instrument forms a basket-like receptacle around the target tissue to excise the target tissue from the ablated tissue mass. As the instrument forms the receptacle, the length of exposed filament ablating the tissue changes. To this end, the RF power generator described herein is configured to vary the total power delivered during the deployment of the instrument based on a measurement of output power derived from a differential phase angle between a current sense output and a voltage sense output, in some embodiments, to maintain a uniform power density along the length of exposed filament.

Abstract: An electrosurgical apparatus and method for cutting and resecting a tissue volume is described. The apparatus includes one or more electrosurgical filaments and capture components deployable by forward extension at or near a forward tip of an elongated shaft of the apparatus to form an elliptical path that defines, with the other capture components, a spheroidal receptacle configured to surround a tissue volume for resection. The elliptical path is formable by a first extension followed by a second extension, said first extension having a first axial component and a radial expansion component, and said second extension having a second axial component and a radial contraction component, where at least one of the capture components is of varying stiffness.

Abstract: The disclosed technology is directed to a RF power generator and feedback control system used to regulate the electrical power delivered to a cutting filament (i.e., a cutting electrode) of an electrosurgical instrument. The electrosurgical instrument uses the delivered energy to form a cutting arc for ablating a tissue mass to access a target tissue therein. The instrument forms a basket-like receptacle around the target tissue to excise the target tissue from the ablated tissue mass. As the instrument forms the receptacle, the length of exposed filament ablating the tissue changes. To this end, the RF power generator described herein is configured to vary the total power delivered during the deployment of the instrument based on a measurement of output power derived from a differential phase angle between a current sense output and a voltage sense output, in some embodiments, to maintain a uniform power density along the length of exposed filament.

Abstract: An electrosurgical apparatus and method for cutting and resecting a tissue volume is described. The apparatus includes one or more electrosurgical filaments and capture components deployable by forward extension at or near a forward tip of an elongated shaft of the apparatus to form an elliptical path that defines, with the other capture components, a spheroidal receptacle configured to surround a tissue volume for resection. The elliptical path is formable by a first extension followed by a second extension, said first extension having a first axial component and a radial expansion component, and said second extension having a second axial component and a radial contraction component, where at least one of the capture components is of varying stiffness.