Diagnostic ultrasound is a noninvasive imaging technique using high frequency sound waves to create echos at the interfaces of tissues of different sound densities.  These echos are monitored and converted to a visual image by electronic transducers.  Ultrasound techniques allow better definition between soft tissues and easier identification of soft tissue lesons than conventional radiography.  Ultrasonic real time units are portable and require no special protective measures.  The image is produced without need of darkrooms or developing and is available for immediate analysis.  These factors make poolside use feasible.

There are many clinical applications of real time (moving image) ultrasound examination.  Obstetrical uses include pregnancy diagnosis, determination of fetal viability and fetal diagnostics. The safety of ultrasound examination for the fetus makes it a primary tool in these applications.  Other uses include the diagnosis of urinary system diseases, liver diseases and even internal abscesses.  The lack of bowel gas in normal marine mammals which greatly complicates radiographic abdominal studies is an asset in ultrasonic examination.  This makes examination of the bowels more feasible in these animals than in any others. Special considerations in equipment and application to marine mammals will be discussed.