Ah I guess in the case of ultrasound, the thing you're trying to do is not nudge or move something, you're literally trying to "ablate" or hit it and only it. T

Ah I guess in the case of ultrasound, the thing you're trying to do is not nudge or move something, you're literally trying to "ablate" or hit it and only it. That's more like pressing a tiny button with your finger and trying not to touch the outside of the button.