Systems, devices, and methods are provided to provide workflow assistance to an operator during a medical imaging procedure, such as a Doppler ultrasound evaluation of a body vessel of a subject. A sensor such as a gyroscope (128) may be integrated in an external ultrasound probe (102). Workflow assistance may be provided to position the ultrasound probe (102) to make accurate flow measurements of fluid within the vessel, such as by coupling system color flow information with gyroscope angles. The workflow assistance may also assist a user in identifying a perpendicular orientation of the ultrasound to be used as a reference in making Doppler measurements. The system may also be used to create a vessel map.