Even before ultrasound became a widespread diagnostic tool, doctors were using it as a
therapeutic tool. The fact that ultrasound does have biological effects on the body is clear from its uses to
promote healing and even to operate on human beings. Ultrasound speeds the healing of bone, although it is
not clear why this occurs. And surgeons are using highly-focused ultrasound beams to operate on delicate
areas such as the eyes. The focused beam heats up and selectively destroys a minute portion of the tissue.
Studying the therapeutic effects of ultrasound could also yield clues to any possible harmful effects of
diagnostic ultrasound.