Power in ultrasound describes the energy generated by a wave or in a signal per unit of time. The power is measured in watts (W) and is proportional to the square of the amplitude.

See also Spatial Average Intensity, Ultrasound Radiation Force and Time Average Intensity.

In power mode the amplitude (power) of color Doppler signals is displayed, regardless of the velocity. Power does not have negative values and is independent of sampling frequency. An aliasing artifact does not occur in power mode images. Caused by plotting the quantity enhanced by echo contrast agents in a power map, power mode is often used in contrast Doppler ultrasound examinations.
Also known as energy mode.

Pressure is the force per unit area applied on a surface in a direction perpendicular to that surface.
Pressure can also be described as a form of potential energy in a fluid. The maximum pressure of the fluid medium obtained during propagation of an ultrasonic pulse.
The negative peak pressure is the peak rarefaction pressure attained during the negative portion of a propagating ultrasound pulse in a medium such as tissue.
Sound pressure can be measured using a microphone in air and a hydrophone in water. The SI unit for sound pressure is the Pascal.
Blood pressure is the pressure exerted by the blood on the walls of the blood vessels.

See also Rarefactional Pressure, Low Intensity Pulsed Ultrasound, and Projector.

A projector (transmitter) converts the energy from the power amplifier (generator) into an acoustic pressure output. Projectors are usually driven near their resonance frequencies where they provide the highest acoustic output.

From Siemens Medical Systems;
'This extremely flexible system supports targeted applications for OB/GYN, Radiology, Internal Medicine, Urology, and Prostate Brachytherapy. The large transducer selection, most with high-frequency capabilities, provides the right tool for general imaging, radiology, and internal medicine applications.'