Abstract

The passage of sound through a medium involves acceleration and displacement of particles in the medium as well as localize forces and stresses. When sound wave transmission is through tissues, the possibilities of biologic effects,no matter how remote, come in to question. It is well known that ultrasound beams of sufficient intensity can modify and even damage biologic tissues. It is n.ot known, however, whether diagnostic ultrasound beams of sufficient intensity can modify and even,damage biologic tissues. It is not known, however, whether diagnostic ultrasound beams produced during clinical studies can cause harmful effects. The vast experience that has been gained with clinical ultrasound equipment has been accompanied by no known tissue damage.