| 摘要 |
An electrosurgical instrument is provided for the treatment of tissue, the instrument comprising an instrument shaft (10) having a longitudinal axis, and an electrode assembly at one end of the shaft. The electrode assembly comprises first and second active electrodes (11), (14) and at least one return electrode (25), the electrodes being electrically insulated one from another by means of one or more insulation members (12). The first and second active electrodes (11, 14) each have an exposed surface for treating tissue, the exposed surface (19) of the first active electrode being such as to treat tissue disposed laterally of the longitudinal axis at a first radial position with respect to the instrument shaft. The exposed surface (15) of the second active electrode is such as to treat tissue disposed laterally of the longitudinal axis at a second radial position with respect to the instrument shaft. The instrument has a first set of connections by which the first active electrode (11) can be placed in circuit with the return electrode (25), and a second set of connections by which the second active electrode (14) can be placed in circuit with the return electrode (25). |
| 主权项 |
1. An electrosurgical instrument including an instrument shaft having a longitudinal axis and an electrode assembly at one end of the shaft, the electrode assembly consisting of:
a first, single active electrode, which is not part of any array of electrodes, the array of electrodes being defined as a plurality of electrodes which are disposed on a same surface of or at a same radial position on any instrument shaft, a second, single active electrode, which is separate from the first electrode and which is not part of the any array of electrodes, and one or more return electrodes, at least a portion of the one or more return electrodes being set back along the longitudinal axis of the instrument with respect to the first active electrode, each of the electrodes being electrically insulated from one another by means of one or more insulation members, the first and second active electrodes each having an exposed surface for treating tissue, the first and second active electrodes each having a different characteristic, in that the distance between the first active electrode and the nearest return electrode is less than that between the second active electrode and the nearest return electrode, such that the first active electrode tends to act as a vaporisation electrode and the second active electrode tends to act as a coagulation electrode, the exposed surface of the first active electrode being positioned so as to treat tissue disposed laterally of the instrument shaft at a first radial position with respect to the longitudinal axis of the instrument shaft, the exposed surface of the second active electrode being positioned so as to treat tissue disposed laterally of the instrument shaft at a second radial position with respect to the longitudinal axis of the instrument shaft, the first and second radial positions being separated by an angle of at least 30°, the instrument further including: a switch, and a switching circuit, which when the switch is manually set to a first position, activates a first set of connections by which the first active electrode is placed in circuit with one of the one or more return electrodes, such that in use a current path is established between the first active electrode and at least one return electrode, and which when the switch is manually set to a second position, activates a second set of connections by which the second active electrode is placed in circuit with one of the one or more return electrodes, such that in use a current path is established between the second active electrode and at least one return electrode. |
