Patent ID: 8556889

Claim:
A microwave ablation system, comprising: an antenna assembly configured to deliver microwave energy from a power source to tissue; a coolant source operably coupled to the power source and configured to selectively provide fluid to the antenna assembly via a fluid path; a controller operably coupled to the power source; a signal processing circuit operably coupled to the controller, comprising: at least one sensor disposed in a resonant feedback loop with an amplifier configured to generate output to a band pass filter centered on a resonant frequency consistent with fluid flow through the fluid path; a sample-and-hold peak detector operably coupled to the output of the band pass filter, wherein the at least one sensor is operably coupled to the fluid path and the signal processing circuit, the at least one sensor configured to detect fluid flow through the fluid path, wherein the signal processing circuit causes the controller to control the power source based on the detected fluid flow during delivery of microwave energy from the power source to tissue.