| 摘要 |
PURPOSE:Not to give thermal damage caused by Joule heat eve if the tip part of an inner needle comes into contact with internal organs in a celom or a celom wall by providing a control means for detecting a fact that the tip part of the inner needle passes through a body wall and stopping electric conduction to an electrode part. CONSTITUTION:In the tip of an inner needle 3 which can be inserted and drawn out freely into and from the inside of a mantle tube 1, a needle-like part 4 pierced into a body wall of an abdominal cavity, etc., is provided so as to protrude from the tip of the mantle tube 1. The inner needle 3 consists of an insulating material except an electrode 5, the electrode 5 is connected mutually in the tip of the needle-like part 4, and a high frequency is subjected to electric conduction through a cable 6 from a high frequency power source unit 7. To the high frequency power source unit 7, a patient plate 9 installed on a body wall of a patient is connected through a cable 8, and when resistance between the electrode 5 and the patient plate 9 becomes infinite, electric conduction to the electrode 5 is stopped, and when the electric conduction stops once, even if there is resistance, no electric conduction is executed. In such a way, even if the tip of the needle-like part 4 comes into contact with internal organs in a celom, a high frequency current does not conduct, and the internal organs are not injured. |
