Real Time Ultrasound Elastography for the Differentiation of Benign and Malignant Thyroid Nodules

Abstract

The purpose of this study was to evaluate the predictive value of real-time ultrasound elastography (RUE) in differentiating benign from malignant thyroid nodules, with fine needle aspiration cytology analysis as the reference standard. A total of 78 consecutive patients with thyroid nodules who were selected for fine needle aspiration biopsies were examined in this prospective study. 78 nodules in these patients were examined by conventional ultrasound, and ultrasound elastography. The final diagnosis was obtained from cytological findings. Tissue stiffness on ultrasound elastography was scored from 1 (low stiffness over the entire nodule) to 5 (high stiffness over the entire nodule and surrounding tissue). On real-time ultrasound elastography, 47 of 62 benign nodules (76%) had a score of 1 or 2, whereas 15 of 16 malignant nodules had a score of 3 to 5, with sensitivity of 93.7%, specificity of 90%, a positive predictive value of 71%, and a negative predictive value of 98%. Real-time ultrasound elastography is a promising imaging technique that is useful in the differential diagnosis of thyroid cancer. Utilization of ultrasound elastography could reduce the rate of thyroid biopsies because of its high elasticity being highly associated with benign cytology.

Elastography: A New Ultrasound Technique in Nodular Thyroid Pathology

“…The following devices using strain elastography: ElaXto (Esaote), RTE (Hitachi Aloka), elastography (General Electric, Philips, Toshiba, Ultrasonix), eSieTocuh: (Samsung, Siemens), respectively, ARFI: VirtualTouch Imaging: (Siemens) are currently present on the commercial ultrasound machine market [30]. It is worth mentioning that the amount of external applied pressure has to be medium and is quantified for each device: for Hitachi machines, the compression scale is displayed always, and the pressure should be between 3 and 4 [31,32]; in Siemens machines, it should be respectively a quality factor about 50 [33] and for Philips devices, it should maintain a steady pressure level displayed on the screen [34].…”