Which diathermy technique involves the active electrode in contact with tissue, applying low current and high voltage?

The diathermy technique that involves the active electrode in contact with tissue, applying low current and high voltage, is referred to as the dessication mode. This technique is utilized to effectively remove or desiccate tissue by causing cellular dehydration. In this mode, the application of low current allows the heat generated from the high voltage to be localized at and near the electrode's contact point, promoting the intended desiccation effect without creating significant charring. This process is particularly useful in surgical procedures for precise and controlled tissue alteration, helping to minimize damage to surrounding structures.

Other modes like coagulation and fulguration involve different applications of energy. Coagulation mode often employs higher current and may not require contact with the tissue, focusing on creating hemostasis. Fulguration, on the other hand, generally involves high-frequency currents that produce sparks to ablate tissue from a distance, which contrasts with the direct contact seen in dessication mode. The blend mode combines features of coagulation and desiccation but does not exclusively focus on direct contact as a defining characteristic. Thus, the unique interaction of low current and high voltage in direct contact with the tissue is what specifically defines the dessication mode.