Ultrasound is used primarily as a medical imaging tool, but scientists are finding more and more uses for these high-frequency sound waves, both in and out of the medical field.

Ultrasound vs. Internal Bleeding
Ultrasound is being harnessed for use in military battles as a way to combat internal bleeding. The Defense Advanced Research Projects Agency (DARPA), the central research and development office for the U.S. Department of Defense, has developed a device that uses ultrasound to halt internal bleeding, cutting down on often-fatal blood loss and shock. The Deep Bleeder Acoustic Coagulation cuff (DBAC) wraps around the wounded limb and delivers ultrasound waves that cause the blood to coagulate, stopping the blood loss.

Ultrasound vs. Punctured Lungs
Being comprised largely of air sacs, lungs are particularly delicate organs, so treatment for punctured lungs is risky business. However, a handheld ultrasound device tested at the University of Washington has proven to be a promising non-invasive option. It heals punctured lungs by focusing ultrasound waves at the puncture location, creating a hot spot similar to a laser beam. The blood cells heat up and form a seal, stopping the loss of air. Unlike lasers, the tissue between the device and the spot being treated does not get hot.

Ultrasound vs. Cancer
Researchers at Oxford and the University of Pennsylvania have tested the effects of ultrasound waves on cancerous tumors, finding that ultrasound is effective in destroying the tumors' blood supply and killing the cancer cells. High Intensity Focused Ultrasound (HIFU) is particularly useful for its high precision and intensity.

Ultrasound vs. Unruly Crowds
Ultrasound has contributed to the development of modern nonlethal weaponry like the Sonic Devestator, a handheld gun that can be used by law enforcement in riots and intense crowd control situations. The gun causes intense discomfort in humans, who may need an hour to recover, but it causes no permanent damage.