Math, myth and the fundamentals of electrosurgery

An electrosurgery generator (ESU) is a critical piece of equipment found in every therapeutic endoscopic setting. The high frequency (RF or Radio Frequency) alternating currents produced by these ubiquitous generators provide the thermal energy used for the treatment of gut diseases from polyps to bile duct stones, strictures, tumors and more. A frequent physician complaint is that even though this technology is widely used, it is not widely understood. Standing in the way of understanding is a lack of education, inconsistency in terminology, persistent myths and incorrect explanations, and unnecessarily confusing and/or outdated teachings. This article attempts to explain in a straightforward manner, using clearly defined terms, some of the basic principles of electrosurgery as applied to gastroenterology. Common myths are highlighted and important mathematical principles critical to the technology are presented.