<unk>  is any of a class of medical imaging modalities that map the elastic properties and stiffness of soft tissue. The main idea is that whether the tissue is hard or soft will give diagnostic information about the presence or status of disease. For example, cancerous tumours will often be harder than the surrounding tissue, and diseased livers are stiffer than healthy ones. The most prominent techniques use ultrasound or magnetic resonance imaging (MRI) to make both the stiffness map and an anatomical image for comparison.
Elastography
Digital variance angiography
Microangiography
Strain rate imaging
Ankle–brachial pressure index
Venography
Digital subtraction angiography
Intravascular imaging