High Frequency Surgery for the Treatment of Herniated Discs

Abstract

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 fluoroscopic control.