Ultrasonic Imaging

Elasticity imaging has emerged as complementary to ultrasonic imaging. The term encompasses a variety of techniques that can depict a mechanical response or property of tissues(91). In ultrasound, its idea is built on two important facts: (a) that significant differences between mechanical properties of several tissue components exist and (b) that the information contained in the coherent scattering, or speckle (speckle is the basis of the texture displayed in ultrasound images of solid tissues which gives it its characteristic grainy appearance), is sufficient to depict these differences following an external or internal mechanical stimulus. Parameters, such as velocity of vibration, displacement, strain, velocity of wave propagation, have all been demonstrated feasible in their estimation and have resulted in the accurate depiction of stiffer tissue masses, such as tumors(91). At physical examination, it has long been recognized that malignant tumors tend to feel hard when compared with benign lesions. US elastography can be used to measure tissue stiffness with the potential to improve specificity in the diagnosis of breast masses. There are two forms of US elastography available today: strain and shear wave.With either technique, acoustic information regarding lesion stiffness is converted into a …show more content…
The strain of subcutaneous fat is determined from a circular area bound by the skin and mammary glands. The strain of a lesion, meanwhile is determined from a circular area bound by the inner margin of the hypo-echoic area, the tumor ROI should be placed entirely in the tumor in B-mode. The target ROI for subcutaneous fat should be limited to fat that does not contain fibro glandular breast tissue at a similar depth to the