High-frequency coagulation, cutting, and coblation technology have long
been applied during endoscopic spine surgery. Endoscopic visualization devices and
high-frequency surgical devices can be found in almost every surgical subspecialty.
During surgical HF applications, electrical energy is converted into heat, used to cut
biological tissue and stop bleeding. This technology works with high voltages in
cutting and coagulation mode. The difference is in the creation of arcs, which have a
cutting effect. In simplified terms, voltages of ≤ 200 Volts are generated during
coagulation and > 200 Volts during cutting. The interaction of HF with biological
tissue can be explained by the faradic, electrolytic, and thermal effect. A frequency of
over 400 kHz has no harmful effect on body tissue. Frequencies over 1MHz have a
“cold cutting effect” allowing for safe bipolar applications and minimizing thermal
damage. This chapter reviews how modern high-frequency generators work and how to
minimize risk during clinical applications, including electrode bonding and burns by
applying automatic power metering, two-part neutral electrode, and bipolar techniques.
During spinal endoscopy, the effects of HF treatment can be directly assessed under
very high magnification factors. This complementary overlap of the videoendoscopic
and HF technique in modern endoscopic spine surgery is the key to superior clinical
outcomes compared to non-visualized percutaneous procedures performed under
Keywords: Coblation, Cutting, Endoscopic surgery, Herniated disc, High frequency.