From Hitachi Medical Systems America Inc.;
The EUB-405 PLUS ultrasound system is a small portable unit and offers extreme dependability and uncompromising image quality. Compatible with a wide range of transducers, this system is a cost effective solution for a variety of clinical settings. A variety of measurements and calculations including distance, area, circumference, volume, are possible.

From Hitachi Medical Systems America Inc.;
The EUB-500 is similar to the EUB-405 PLUS. Added features are the 12-inch monitor, the second probe port, cine memory, gain slide control/multifunction trackball.

Hitachi Medical Systems America Inc.;
The EUB-525 is a mid-size ultrasound system with a full feature set. Capable of B-mode, M-mode, Doppler, color flow and color angiography it performs a variety of tasks in a simple and straightforward fashion. This system produces high quality images with excellent clarity and detail.

Echogenicity is the ability of a medium to create an echo, for example to return a signal when tissue is in the path of the sound beam. The ultrasound echogenicity is dependent on characteristics of tissues or contrast agents and is measured by calculating the backscattering and transmission coefficients as a function of frequency.
The fundamental parameters that determine echogenicity are density and compressibility. Blood is two to three orders of magnitude less echogenic than tissue due to the relatively small impedance differences between red blood cells and plasma. The tissue echogenicity can be increased by ultrasound contrast agents. Encapsulated microbubbles are highly echogenic due to differences in their compressibility and density, compared to tissue or plasma.
Microbubbles are 10,000 times more compressible than red blood cells. The compressibility of air is 7.65 x 10−6 m2/N, in comparison with 4.5 x 10-11 m2/N for water (on the same order of magnitude as tissue and plasma). This impedance mismatch results in a very high echogenicity. An echo from an individual contrast agent can be detected by a clinical ultrasound system sensitive to a volume on the order of 0.004 pl.

See also Isoechogenic, Retrolenticular Afterglow, and Sonographic Features.

Echography (also called sonography) allows visualizing deep structures of the body by recording the reflections (echo) of ultrasound waves directed into the tissues. A medical diagnostic sonogram (echogram), as in echocardiography and echoencephalography, utilizes a frequency range of 1 to 10 MHz.