Color assignments can be switched on any ultrasound system and are used as directional indicators. The colors of red and blue indicates flow direction in color Doppler.
Red is encoded to represent flows toward the transducer.
Blue pixel encoding is used to depict flows away from the transducer.

See also Directional Color Power Doppler.

Ultrasound imaging is excellent for diagnosing cysts and other fluids in soft tissue. For ultrasound imaging or ultrasonography, different modes are used to examine the arterial/venous system, heart, pancreas, urinary system, ovaries, spinal cord, joints and more.
Power levels, frequencies used, amplification, and beamforming determine the clarity of the image. These things are controlled by the sonographer, interacting with the properties of the ultrasound machine.

Various imaging modes:

From Philips Medical Systems;
Introduced in June 2005, 'one of the less expensive and more dedicated' ultrasound systems.

From ALOKA Co., Ltd.;
'A Platform for Digital, Pure-Beam Imaging The high-performance, ALOKA ProSound SSD-3500 utilizes advanced ProSound technologies including:
Fully digital beam former A wide dynamic range, 12-bit A/D converter Multi beam processing.
The SSD-3500 also helps you achieve more efficient examinations. Its ergonomic, user-friendly design enables you to customize the system according to your specific application needs.'

From Fukuda Denshi Co., Ltd.;
'Fully software controlled Image Processing (F-XT technology)
Color Doppler & Power Doppler display available
Autofocus function for transmission
High-resolution SVGA display
Cine memory with 128 frames
Wide band Probe for multi frequency function
6-step STC adjustment
DICOM-compatible Ethernet port
3.5-inch 640MB drive for image filing'