US Patent 7261695 Trigger extraction from ultrasound doppler signals

A trigger extraction system for obtaining an event trigger for an event occurring in a region of interest includes a processor, a memory coupled to the processor, and a trigger extraction program stored in the memory for execution by the processor. The trigger extraction program includes instructions for accessing ultrasound trigger data from a trigger region intersecting a region of interest, analyzing the trigger data for a trigger characteristic, and storing an event trigger based on the trigger characteristic.