Electrosurgery With Cellular Precision

Abstract

Electrosurgery, one of the most-often used surgical tools, is a robust but somewhat crude technology that has changed surprisingly little since its invention almost a century ago. Continuous radiofrequency is still used for tissue cutting, with thermal damage extending to hundreds of micrometers. In contrast, lasers developed 70 years later, have been constantly perfected, and the laser-tissue interactions explored in great detail, which has allowed tissue ablation with cellular precision in many laser applications. We discuss mechanisms of tissue damage by electric field, and demonstrate that electrosurgery with properly optimized waveforms and microelectrodes can rival many advanced lasers. Pulsed electric waveforms with burst durations ranging from 10 to 100 micros applied via insulated planar electrodes with 12 microm wide exposed edges produced plasma-mediated dissection of tissues with the collateral damage zone ranging from 2 to 10 microm. Length of the electrodes can vary from micrometers to centimeters and all types of soft tissues-from membranes to cartilage and skin could be dissected in liquid medium and in a dry field. This technology may allow for major improvements in outcomes of the current surgical procedures and development of much more refined surgical techniques.

Comparative Healing of Rat Fascia Following Incision with Three Surgical Instruments

“…Recently, the use of brief (40-ms range), highfrequency pulses of RF energy to induce the formation of electrical plasma along the edge of a thin (approximately 12 mm wide), flat, 99.5 percent-insulated electrode, has demonstrated the ability to effectively cut and coagulate tissue with significantly decreased thermal damage [14,15]. By limiting the pulse repetition rate to less than 1 kHz, and the duty cycle (fraction of time that energy is delivered to the electrode) to less than 5%, efficient cooling of the electrode is achieved and the operating temperature remains between 40 C and 100 C (traditional electrosurgery is typically 250 C to 350 C).…”

Comparative Healing of Surgical Incisions Created by the PEAK PlasmaBlade, Conventional Electrosurgery, and a Scalpel

“…The radiofrequency pulses induce a plasma-mediated discharge along the exposed edge of a thin (10 to 50 m), flat, 99.5 percent insulated electrode. 14,15 This plasma rim provides a cutting edge for precise tissue dissection with simultaneous hemostasis. Because of the reduced duty cycle and the small exposed area of the electrode, pulsed electron avalanche knife technology yields a much lower average power output and uses less total energy than conventional electrosurgery to achieve an equivalent rate of tissue cutting, thus reducing collateral thermal damage.…”

“…Because of the reduced duty cycle and the small exposed area of the electrode, pulsed electron avalanche knife technology yields a much lower average power output and uses less total energy than conventional electrosurgery to achieve an equivalent rate of tissue cutting, thus reducing collateral thermal damage. 14,15 Although pulsed electron avalanche knife technology has been evaluated previously on ophthalmic tissues, 13,16 -21 its effects on cutaneous wound healing remain unknown.…”

Energy based surgical instruments : With particular focus on collateral thermal injury

“…Large di erences are reported in thermal spread of EBDs, ranging from a few millimeters [34,119,121,131] to one cm or more [132]. is disparity in values highlights the di culty in de ning safety distances for EBDs, as safety in surgery is much more, than just what kind of EBD the surgeon uses during the operation.…”