The working principles of ordinary high-frequency electrosurgical units and RF-grade high-frequency electrosurgical units are different, resulting in different environments where they can work.

The working principle of high frequency electrosurgery is Ohm's law. When electrical current is passed through human tissue, heat is generated due to the impedance of the tissue. When the current is constant, the greater the impedance, the greater the heat. The cells are ruptured by heat to achieve the purpose of ablation.

The working principle of the RF-grade high-frequency electrosurgical knife is that the working end of the electrode outputs high-frequency electromagnetic waves, which are concentrated in a small area. Under the action of this local high-frequency electromagnetic field, the water molecules oscillate rapidly and rub against each other, causing the intracellular water to evaporate, vaporize, dry the tissue, shrink and cause aseptic necrosis, thereby achieving the purpose of ablation.

The foramenoscope needs to be flushed with normal saline during work to ensure the clarity of the foramoscope. Physiological saline is a solution of sodium chloride, which contains sodium and chloride ions, and is a conductive solution.

When the high-frequency electrosurgical knife works under the foramen microscope, flushing with normal saline will cause a short circuit, reduce the impedance, and lose its effectiveness.

The RF-grade high-frequency electrosurgical knife outputs RF through the high-frequency endoscopic surgical electrode, and the electrode has two poles at the working end, forming a self-closed loop, which can work in a liquid environment and ensure safety.