| abstract |
An electrosurgical generator has output terminals for connection to active and returnnelectrodes respectively of an electrosurgical instrument and, connected to the outputnterminals via at least one isolation capacitor, a radio frequency (r.f.) source which maynbe pulsed by a pulsing circuit. To permit tissue removal at a high rate, the source andnthe pulsing circuit are arranged so as to generate a pulsed r.f. output signal having anpeak-to-peak voltage of at least 1250V, a mark-to-space ratio not more than 1:1, and anpulse length not more than 100µs. n A continuous RF wave applied to the cutting electrode would in factnrapidly bring the electrode to high operating temperatures which couldncause electrode destruction since the rate at which heat is accumulatednon to the electrode would be higher that the heat dissipation rate innthe operating environment. n The pulsed RF wave allows during the off periods for heatndissipation, temperature decrease, thus electrode conservation andnhigher peak power thus higher cutting speeds. |