Elastography - the movement begins

The advent of real-time ultrasound in the 1970s, together with a growing in terest in tissue characterization, led to a number of investigators using t he nature of tissue motion to distinguish healthy from diseased tissue. Our group at the (then) Ultrasonics Institute demonstrated the use of phase me thods for detecting very small tissue motions, using natural stimuli. The m ethod could also be applied in the lag (autocorrelation) domain to directly measure the amount of deformation to high accuracy. This method was also a pplied to measuring the amount of dilatation of blood vessels using both co nventional and intravascular ultrasound. A basic limitation of these techni ques was the poor spatial resolution, and quasistatic methods soon replaced this method of measuring tissue deformation. However, a new way of assessi ng the health of tissues had been established.