A microcatheter for removing thromboemboli from
cerebral arteries in patients suffering from
ischemic stroke. The microcatheter provides an extraction lumen that can be scaled to a very small
diameter that is still capable of extracting and emulsifying
thrombus without clogging the channel. The microcatheter of the invention uses a series of spaced apart energy application mechanisms along the entire length of the
catheter's extraction lumen to develop sequential pressure differentials to cause fluid flows by means of
cavitation, and to contemporaneously ablate embolic materials drawn through the extraction lumen by
cavitation to thereby preventing clogging of the lumen. The
catheter system thus provides a functional high-pressure extraction lumen that is far smaller than prior art
catheter systems. Preferred mechanisms for
energy delivery are (i) a
laser source and controller coupled to optic fibers in the catheter wall or (ii) an Rf source coupled to paired electrodes within the extraction lumen. Each energy emitter can apply energy to fluid media in the extraction channel of the catheter-wherein the intense energy pulses can be sequentially timed to cause fluid media flows in the proximal direction in the channel.