ABSTRACT
High-frequency alternating current is passed through the body intentionally for electrosurgery and diathermy. In the former case, localized heating is produced at the tip of a hand-held probe to cut and coagulate tissue. Electrosurgical techniques use 0.5-2 MHz radio-frequency current delivered to the tissue by a hand-held probe to dessicate, coagulate and cut living tissue. Two types of radio-frequency current are used to induce the three types of tissue response. There are two techniques for applying the hand-held probe, also called the active electrode or pencil: one brings the tip of the probe in contact with the tissue, then the electrosurgical unit (ESU) is activated. Dessication, i.e. drying, is produced by placing the tip of the probe in contact with the tissue to be desiccated and activating the ESU. Coagulation employs modulated current and several different techniques are employed with the active electrode.
