ASSESSING THE RISKS FOR MODERN DIAGNOSTIC ULTRASOUND IMAGING

Some 35 years after Paul-Jacques and Pierre Curie discovered piezoelec tricity, ultrasonic imaging was developed by Paul Langevin. During thi s work, ultrasonic energy was observed to have a detrimental biologica l effect. These observations were confirmed a decade later by R. W. Wo od and A. L. Loomis. It was not until the early 1950s that ultrasonic exposure conditions were controlled and specified so that studies coul d focus on the mechanisms by which ultrasound influenced biological ma terials. In the late 1940s, pioneering work was initiated to image the human body by ultrasonic techniques. These engineers and physicians w ere aware of the deleterious ultrasound effects at sufficiently high l evels. this endeavored them to keep the exposure levels reasonably low . Over the past three decades, diagnostic ultrasound has become a soph isticated technology. Yet, our understanding of the potential risks ha s not changed appreciably. It is very encouraging that human injury ha s never been attributed to clinical practice of diagnostic ultrasound.