Diagnosis of Thyroid Nodules by Elastography

Ultrasonography is mandatory for the evaluation of thyroid nodules. Although B-mode and Doppler ultrasonography are both sensitive for the diagnosis of thyroid lesions, they lack specificity in differentiating benign from malignant nodules. Elastography has been described as an accurate predictor of malignancy by determining tissue elasticity. There are several meth-ods utilized to evaluate the stiffness of normal tissue and the thyroid nodule, such as strain elastography, acoustic radiation force impulse, and shear wave elastography. Many studies show that elastography has both high sensitivity and specificity that approaches 100% for the determination of thyroid carcinoma. In addition, elastography also has a very high negative predictive value and thus, may also be helpful in the identification of thyroid nodules that do not need further diagnostic evaluation, including fine needle aspiration cytology. However, in the light of current evidence, there is a need for standardization and consensus on the most optimum elastography acquisition process. The purpose of this review is to provide a com-prehensive summary of the use of elastography in the evaluation of thyroid nodules.