WHAT IS ELASTOGRAPHY?
Elastography is one of the clinical techniques that maps the elastic properties and stiffness of soft tissue. It is a medical image modality that gives diagnostic information about the stiffness of the organ's tissue.
Elastography is especially used to diagnose the diseases in the liver. The stiffness within the liver is usually indicative of fibrosis or steatosis, which indicates about the diseases within it. Elastography comes as an advantage in this condition because when fibrosis is diffuse, a biopsy can easily miss sampling the diseased tissue, which results in a false negative misdiagnosis.
WHAT IS ARFI?
There are many different types of ultrasounds elastography. One of them is ARFI (Acoustic radiation force impulse imaging). It creates a qualitative 2-D map of tissue stiffness using an ultrasound. The process is done by creating a push inside the tissue using the acoustic radiation force from a focused ultrasound beam. The stiffness (hardness or softness)of the tissue is defined by the amount the tissue along the axis of the beam is pushed down. Softer tissue is more easily pushed than stiffer tissue. The ARFI elastography displays a qualitative stiffness value along the axis of the pushing beam. A tissue map is created by pushing the tissue in many different places.