What Is the Difference in an Ultrasound & Extracorporeal Shockwave Therapy?

Ultrasounds are used for imaging. Shockwave therapy is used to treat kidney stones.

Ultrasound technology uses sound waves bouncing off tissues to look inside the body without the need for surgery. Computer technology aids this process by interpreting the sound waves being reflected and making an image from them. Extracorporeal shock wave therapy (ESWT) also replaces surgery and uses sound, except that it is not an imaging technology. ESWT uses sound waves to obliterate small objects within the body without the need to do it mechanically.

Ultrasound

Sound travels through solid objects at different speeds depending on the density of the objects. Sound also bounces off solid objects and liquids. Ultrasound imaging uses a computer to analyze the echoes given off as sound travels through the body. For example, bone tissue bounces off more sound than would a soft organ like the liver. The "ultra" in ultrasound comes from the fact that the sound wave frequencies being used are beyond ("ultra") frequencies that humans can hear.

Ultrasound Uses

Ultrasound technology is used in cases where surgery is not desirable and x-rays will not do. X-rays are for visualizing bones and high-density structures. On the other hand, ultrasound imaging can help health care providers visualize soft tissues and organs, such as the liver, kidneys or uterus. The process is non-invasive, but it requires a very well-trained technician to perform the procedure and help interpret the results.

Extracorporeal Shock Wave Therapy

ESWT also uses sound waves. The sound waves are of very high frequency, even more so than those used for ultrasound imaging. The sound waves are aimed exactly at a spot within the body to obliterate an undesired structure. The high-frequency sound waves pass easily through the soft tissues of the body but crash into solid structures like bone or mineral deposits.

ESWT for Treatment

Kidney stones and bone spurs are mineral deposits in the body that may cause pain or, in the case of kidney stones, a dangerous condition that may damage the kidneys. ESWT may be used when surgery may not be recommended or absolutely necessary. During an ESWT session, the therapist will aim the sound wave at the bone spur or kidney stone and shoot the sound waves. The high-frequency waves strike the minerals and dissolve them into smaller pieces that can be passed or absorbed by the body.

Other Uses for Sound

Sound waves have other uses beyond medicine. Sound waves may be used as weapons, destroying larger targets like they destroy kidney stones. They are already being used in sonar to see objects underwater. New technologies are being researched for other uses for sound waves.

References

• Extracorporeal Shock Wave Lithotripsy Treatment
• General Ultrasound Imaging