Electrosurgical instrument

Abstract

An electrosurgical instrument is manufactured by presenting an electrode ( 1 ), and attaching a sacrificial portion ( 6 ) to the electrode ( 1 ) to form a first electrode assembly. An insulating material ( 9 ) is moulded over the first electrode assembly to form a second electrode assembly, and the second electrode assembly is subjected to a further process which is capable of removing the sacrificial portion ( 6 ) without removing the insulating material ( 9 ). The sacrificial portion ( 6 ) is removed to form at least one cavity within the electrosurgical instrument.

1 . A method of manufacturing an electrosurgical instrument including:
 presenting an electrode,   attaching a sacrificial portion to the electrode to form a first electrode assembly,   moulding an insulating material over the first electrode assembly to form a second electrode assembly, and   subjecting the second electrode assembly to a further process which is capable of removing the sacrificial portion without removing the insulating material,   the sacrificial portion being removed to form at least one cavity within the electrosurgical instrument.   
     
     
         2 . A method according to  claim 1 , wherein the further process is a heat treatment process. 
     
     
         3 . A method according to  claim 1 , wherein the sacrificial portion is removed to form a suction passage within the electrosurgical instrument. 
     
     
         4 . A method according to  claim 1 , wherein the sacrificial portion is coated on to at least part of the electrode. 
     
     
         5 . A method according to  claim 1 , wherein the sacrificial portion is moulded on to at least part of the electrode. 
     
     
         6 . A method according to  claim 1 , wherein the sacrificial portion is formed of a plastics material. 
     
     
         7 . A method according to  claim 1 , wherein the electrode includes a tissue treatment portion and a connection portion, the insulating material is moulded into a component having a first portion and a second portion, the first portion is moulded around the tissue treatment portion of the electrode, and the second portion is moulded over the connection portion of the electrode. 
     
     
         8 . A method according to  claim 1 , wherein the moulding comprises injection moulding the insulating material over the electrode. 
     
     
         9 . A method according to  claim 1 , wherein the insulating material is a ceramic material. 
     
     
         10 . A method according to  claim 9 , further comprising sintering the ceramic material after it has been moulded over the electrode. 
     
     
         11 . A method according to  claim 10 , wherein the sacrificial portion is removed during the sintering of the ceramic insulating material. 
     
     
         12 . An electrosurgical instrument comprising an electrode, the electrode being embedded in an electrically insulating material moulded around the electrode, the electrosurgical instrument having at least one cavity, the cavity having been formed by the removal of a sacrificial material during a manufacturing process without removal of the surrounding insulating material. 
     
     
         13 . An electrosurgical instrument according to  claim 12 , wherein the manufacturing process is a heat treatment process. 
     
     
         14 . An electrosurgical instrument according to  claim 12 , wherein the cavity forms a suction passage within the electrosurgical instrument.