If you're in serious need of super quick recovery and are willing to fork up the cash, then sure, getting ultrasound can speed things up. Otherwise, stick to what Crazy said.
And if you're consistently respraining your ankle, then there are steps you should be taking for future prevention. After damaging the ligament repeatedly, it's now in a permanently loose state, so you need to compensate by increasing the strength of the surrounding muscles to stabilize the joint. One-legged exercise and balance training, as a general note, is what will help you out the most.