Q: What is the difference between therapeutic and diagnostic ultrasound?
Asked by Caitlin White
A: Diagnostic ultrasound involves the use of ultrasound waves to produce an image that will aid in the diagnosis of a particular condition or disease.
It is a tool to aid in the visualisation of internal organs and can be a guide in making informed therapeutic decisions. Ultrasound equipment is designed to obtain information without intentionally producing a biological effect in the tissues. Examples of diagnostic ultrasounds include abdominal ultrasound, thoracic ultrasound, musculoskeletal ultrasound and reproductive system ultrasound.
Therapeutic ultrasound uses sound waves generated by a transducer head to penetrate into soft tissues. It is divided into thermal and mechanical ultrasound therapy. Thermal ultrasound therapy uses a continuous transmission of sound waves that causes microscopic vibrations in deep tissue molecules, increasing heat and friction.
Mechanical ultrasound therapy uses pulses of sound waves to penetrate tissues, has a minor warming effect, causes expansion and contraction in tiny gas bubbles within soft tissues, and helps decrease the inflammatory response, reducing tissue swelling and thus decreasing pain. This is particularly useful for treatment of swelling and scar tissue.
Answered by Onderstepoort Veterinary Academic Hospital.