Electrosurgical Methods and Devices Employing Phase-Controlled Radiofrequency Energy

Abstract

This disclosure relates generally to electrosurgical methods and devices. In some embodiments, an electrosurgical system/device is provided suitable for applying phase controlled RF energy to a treatment site. The electrosurgical device comprises a multi-electrode electrosurgical probe electrically coupled to a plurality of RF generators. Also provided are methods of use of such an electrosurgical device, as well as other electrosurgical devices. The methods and devices disclosed herein find utility, for example, in the field of medicine.

What is claimed is: 
     
         1 . A method for delivering energy to a target site of a patient comprising placing a cannula within close proximity of the target site and delivering phase controlled RF energy to the cannula. 
     
     
         2 . The method of  claim 1 , wherein the target site is tissue, the cannula includes one or more electrode pairs and the energy increases the temperature of the tissue in the region of tissue adjacent the cannula. 
     
     
         3 . The method of  claim 1 , wherein the cannula contacts the target site. 
     
     
         4 . The method of  claim 1 , wherein the cannula creates an electric field having properties that are determined at least in part by the phase between a first electrode pair on the cannula and a second electrode pair on the cannula. 
     
     
         5 . The method of  claim 4 , further comprising at least one of the following:
 actively adjusting the phase between the first electrode pair and the second electrode pair while the cannula is in close proximity to the target site,   actively adjusting the phase controlled RF energy to the cannula in response to a measured parameter of the target site,   applying topical anesthetic to the target site,   applying a liquid or gas to the target site to regulate the temperature of the target site,   applying a conductive liquid or gel between the cannula and the target site,   applying light energy to the target site,   applying ultrasound energy to the target site, or   any combination thereof.   
     
     
         6 . The method of  claim 5 , wherein the target site is living tissue and the measured parameter is the impedance of the tissue. 
     
     
         7 . The method of  claim 4 , wherein the phase between the first electrode pair and the second electrode pair is held constant while the cannula is in close proximity to the target site. 
     
     
         8 . The method of  claim 4 , wherein the phase between the first electrode pair and the second electrode pair is varied while the cannula is in close proximity to the target site. 
     
     
         9 . The method of  claim 1 , wherein the target site is a sweat gland, a sebaceous gland or a combination thereof 
     
     
         10 . The method of  claim 9 , wherein the phase controlled RF energy delivered to the cannula increases the temperature of the gland. 
     
     
         11 . The method of  claim 3 , wherein the target site is skin, and wherein the phase controlled RF energy non-homogeneously increases the temperature of the tissue adjacent the cannula. 
     
     
         12 . The method of  claim 1 , wherein cannula includes two or more cylindrical electrodes arranged substantially in line such that heat is generated in a three (3) dimensional form from an external side of a first electrode to the external side of a second electrode. 
     
     
         13 . The method of  claim 1 , wherein the cannula is a single-use cannula. 
     
     
         14 . The method of  claim 1 , wherein the cannula includes a plurality of ring electrodes arranged in one or more groups of electrodes. 
     
     
         15 . The method of  claim 14 , wherein the plurality of ring electrodes are arranged two or more groups of electrodes each having one or more electrodes. 
     
     
         16 . The method of  claim 14 , wherein the groups of electrodes are predetermined distance apart from each other. 
     
     
         17 . The method of  claim 1 , the method further comprising treating cutaneous and/or sub-cutaneous tissue for the treatment of subcutaneous fat liquefaction, skin tightening, vascular disease, and varicose veins. 
     
     
         18 . An electrosurgical system comprising:
 (a) a cannula for applying at least a heat treatment to tissue of a patient, the cannula being configured with a plurality of electrodes arranged substantially in line, the plurality of electrodes including at least a first electrode, a second electrode and a third electrode; and   (b) one or more RF generators comprising a plurality of outputs and phase shifting circuitry for controlling the phase between the plurality of outputs,   wherein the connection between the plurality of outputs and the plurality of electrodes is configured such that at least one electrode pairing is formed, the at least one electrode pairing including a first electrode pair comprising the first electrode and the second electrode, the first electrode and third electrode or the second electrode and third electrode,   wherein the phase shifting circuitry is configured such that the plurality of outputs apply a respective RF electrical potential across the at least one electrode pairing, and   wherein the RF electrical potential across the at least one electrode pairing causes heating of the tissue of the patient.   
     
     
         19 . The electrosurgical system of  claim 18 , wherein any two of the plurality of electrodes may be electrically coupled to any of the plurality of outputs of the one or more RF generators. 
     
     
         20 . The electrosurgical system of  claim 18 , wherein the at least a heat treatment includes delivering RF energy to the cannula. 
     
     
         21 . The electrosurgical system of  claim 18 , wherein the tissue includes a sweat gland, a sebaceous gland or a combination thereof. 
     
     
         22 . The electrosurgical system of  claim 21 , wherein the phase controlled RF energy delivered to the cannula increases the temperature of the gland. 
     
     
         23 . The electrosurgical system of  claim 18 , further comprising at least one of:
 means for applying light energy to one or more sweat glands or sebaceous glands of the patient,   means for applying ultrasound energy to one or more sweat glands or sebaceous glands of the patient,   means for applying a temperature-regulating liquid or gas to one or more sweat glands or sebaceous glands of the patient,   means for adjusting the RF power delivered by one or more of the plurality of RF outputs in response to a measured parameter.   
     
     
         24 . The electrosurgical system of  claim 23 , wherein the measured parameter is the electrical impedance of tissue of the patient. 
     
     
         25 . The electrosurgical system of  claim 18 , wherein the system is further arranged to deliver a therapeutic compound to one or more sweat glands or sebaceous glands of the patient. 
     
     
         26 . The electrosurgical system of  claim 18 , wherein RF energy is applied by the cannula to the tissue of the patient after tumescent local anesthetic has been injected into the tissue. 
     
     
         27 . The electrosurgical system of  claim 18 , wherein RF energy is applied by the cannula to the tissue of the patient in combination with at least one of a (i) coupling solution, (ii) water-based treatment gel, tap water or baby oil, (iii) a treatment compound having anti-perspirant activity or (iv) a treatment compound having anti-acne or anti-seborrhoeic activity. 
     
     
         28 . The electrosurgical system of  claim 27 , wherein the treatment compound having anti-perspirant activity is aluminum hexhydrate. 
     
     
         29 . The electrosurgical system of  claim 27 , wherein the treatment compound having anti-acne or anti-seborrhoeic activity is selected from the group consisting of salicylic acid and benzyl peroxide.