Patent ID: 7828754

Claim:
An ultrasonic cerebral infarction therapeutic apparatus that dissolves thrombus by irradiating an ultrasonic wave through the cranium to an embolic site of the cerebral blood vessel in the cranium, comprising: an ultrasonic irradiation device equipped with one or a plurality of ultrasonic transducers constructed to cover a part or the whole of the head of a patient under therapy; a high frequency oscillator that supplies a high frequency signal for activating the ultrasonic transducers; a switching device for selecting one or several ultrasonic transducers that are suitable to irradiate the ultrasonic wave toward the embolic site from among the one or the plurality of ultrasonic transducers; and a control device for supplying a high frequency signal outputted from the high frequency oscillator to the one or the plurality of ultrasonic transducers selected by the switching device; wherein the high frequency signal supplied from the high frequency oscillator is selected from one of following waves: (1) a frequency-modulated continuous sinusoidal wave that does not maintain the same frequency for a time longer than 1 ms, (2) a burst wave such that each one of signals constituting the burst wave has an excitation duration of less than 1 ms, (3) a pulse wave such that each one of pulses constituting the pulse wave has an excitation duration of less than 1 ms, and wherein repetition of said excitation duration period is 1 ms or less.