Medical ultrasonics: As new techniques are perfected, ultrasound extends its usefulness from diagnosis to research, therapy, and even surgery

One of the most widely used electronic techniques in medicine today is ultrasound. Physicians using it can now measure the velocity of blood flow in high-risk pregnancies; examine the brains of newborn babies; take motion pictures of a patient's heart; and detect cancerous tumors and the plaques in blood vessels that cause arteriosclerosis. In obstetrics the use of ultrasound has become routine; it is believed that today as many as 40 percent of pregnant women in the United States have at least one such scan.