Elastography is a mathematical technique, which measures the axial elasticity or compressibility. A colored map is used to show the spectrum of the elastic properties of the tissues. In elastographic imaging, soft or highly compressible tissue is shown as red and hard or non compressible tissues are blue. Yellow to green represents tissue elasticity in the middle of the spectrum. Disease processes can alter the inherent baseline elastic property of the tissue. This alteration can be imaged by elastography.
Differentiating malignant from benign lesions
A hybrid combination of high frequency conventional ultrasound imaging with ultrasound elastography can provide anatomical and functional information respectively to characterize the lesion of interest. High frequency ultrasound elastography has the potential to differentiate malignant lesions from benign. Malignant lesions are believed to decrease the elasticity of the effected tissue more than that of the benign lesions. Therefore, on elastographic images, malignant lesions are harder in axial compressibility compared to benign lesions. This alteration can be quantified on elastograhic images.
Future Directions
Sheer wave elastography and MR elastography show tremendous potential in primary skin imaging to achieve a more precise and accurate quantified elastographic characterization of skin lesions.