In ultrasonography, a signal generator is combined with a transducer. Piezoelectric crystals in the signal generator convert electricity into high-frequency sound waves, which are sent into tissues. The tissues scatter, reflect, and absorb the sound waves to various degrees. The sound waves that are reflected back (echoes) are converted into electric signals. A computer analyzes the signals and displays the information on a screen.
Frequency used ranges from 1 to 10 MHz
Ultrasonography is portable, widely available, and safe. No radiation is used.
- Principles of ultrasonography. – S. Hassani (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2609158)
- Ultrasound: Basic understanding and learning the language – Barys Ihnatsenka and André Pierre Boezaart (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3063344)