ELECTROMAGNETIC-FIELD FOCUSING INSTRUMENT AUGMENTS RESECTION OF MENINGIOMAS

THE ELECTROMAGNETIC FIELD focusing (EFF) surgical instrument creates a n oscillating electromagnetic field that induces eddy currents in the tissue, which converge at the point of contact. This energy creates a focal spark capable of vaporizing tissue. The EFF instrument was used to resect 17 meningiomas in 14 patients. The effectiveness of the EFF probe in resecting tumor tissue was compared with that of the Cavetron ultrasonic surgical aspirator (Model 100) in 11 patients. The EFF sys tem was superior to the Cavetron ultrasonic surgical aspirator in tumo r excision in all but two cases, in which the EFF grounding tip was po orly tuned. Surgical time and blood loss were reduced by subjective an alysis in all but these two cases, especially in the rubbery or calcif ied meningiomas resistant to aspiration. No complications were directl y attributable to use of the EFF. Drawbacks encountered with the EFF s ystem include buildup of ''char'' on the tip, requiring scraping, and intense heat at the tip, which occasionally melted the insulating shea th, requiring replacement.