Elastic diagnosis

Doctors have, for many years, relied on manual palpitation to differentiate between different tissues in the human body due to the way they respond to stress. For example, researchers have discovered that tumours have different elastic properties from healthy tissues and that benign and malignant tumours have different responses to shearing stresses (malignant live tumours have greater average shear stiffness than benign ones).

In a development of manual palpitation techniques, researchers have discovered a number of different approaches to precisely measuring the response of tissues to applied stress, a technique known as elastography. Rather than using a doctor’s fingers, in quantitative techniques stresses are applied either by physiological processes, such as the pulse or by artificial stimuli such as ultrasound. The tissue’s response to the applied stresses can be detected using mechanical sensors such as accelerometers, or with ultrasound or magnetic resonance imaging.