Ultrasonography is the second most commonly used imaging technique in veterinary practice. Ultrasonic sound waves are used to create images of body structures produced using the pattern of echoes reflected back from whatever is being imaged.

Unlike radiography, ultrasonography cannot be used to scan gas-filled or bony structures, as these totally reflect or absorb the sound waves. Other organs can also become ‘shadowed’ by gas or bone if lying between the scanner & the organ in question. For example the heart cannot be viewed if the sound beam has to pass through the lungs, and some abdominal organs cannot be visualised due to bowel gas blocking the way!

In the clinic ultrasound is most commonly used to visualise the bladder (to help obtain a sterile urine sample or identify disease), the liver, kidneys and spleen (for identifying disease), the abdomen (for detecting fluid or visualising organs/detecting disease) and the reproductive tract in females (for pregnancy detection, litter size estimation, during whelping/queening or identifying disease)