described in FIG. 3A. An oscillating jet of fluid may be discharged from flow diverting portion 72. [0078] Flow oscillator 62 also includes an oscillating portion 78 configured to oscillate in response to the oscillating pressure differential. As explained above, flow diverting portion 72 creates an oscillating pressure differential that produces an oscillating jet of fluid. Oscillating portion 78 may include an oscillation structure 80 and at least one amplification structure 82. Oscillating structure 80 may be configured to oscillate in response to oscillation of the oscillating jet. For example, oscillating structure 80 may include a pivot or flexible structure that allows oscillating structure 80 to oscillate in response to oscillations of the oscillating jet. Amplification structure 82 may be configured to contact oscillating structure 80 to increase an amplitude of vibration caused by the oscillating jet. For example, as a flow rate of the oscillating jet increases, a magnitude of impact of oscillating structure 80 on amplification structure 82 may increase, such that an amplitude of vibration may increase. In some examples, oscillating structure 80 comprises at least one of a flap, a roller, a ball, or a paddle, or combinations thereof. In this way, vibrations caused by oscillating flow of fluid oscillator 62 may be modified. These oscillations may generate vibrations, such as may be felt on housing 84. [0079] FIG. 4 is a flow diagram of an example method of aspiration that includes generating flow-induced vibrations using a fluid flow sensor in response to receiving fluid flow from a catheter. The techniques of FIG. 4 are described with reference to the various aspects of aspiration system 10 of FIG. 1 for illustrative purposes, however, such descriptions are not intended to be limiting and the techniques of FIG. 4 may be used to form other aspiration systems. The technique of FIG. 4 include introducing catheter 12 into vasculature of the patient (90) and aspirating a thrombus by generating negative pressure on catheter 12 (92), and initiating flow of fluid from catheter 12 to fluid pump 18 (94), thereby generating vibrations in response to flow of fluid through fluid flow sensor 16. In some examples, the techniques described herein include removing catheter 10 from the vasculature of the patient once the procedure is complete. [0080] In some examples, introducing catheter 10 into vasculature of a patient (90) may be aided by initially introducing a guidewire, guide catheter or another guide member into the vasculature of the patient to a target treatment site. An elongated body of catheter 12 may then be introduced over the guidewire and advanced to the target treatment site. Additionally, or alternatively, catheter 12 may be introduced into vasculature of a patient via the aid of a guide catheter. For example, that the guide