Figure 1.
B-mode ultrasound of the right lobe of thyroid gland using the S2000, 9L4 probe at 9 MHz with the ROI placed within the healthy thyroid tissue measuring an ARFI velocity of 1.90 m/s.
Figure 2.
Acoustic Radiation Force Impulse Imaging (S2000, 9L4 probe at 9 MHz) of the same patient a in
Figure 1 with the ROI placed within a hypoechoic thyroid nodule in the right thyroid lobe measuring a velocity of 6.24 m/s. Histology revealed papillary carcinoma.
Table 1.
Patient characteristics.
Table 2.
Senstivity, specificity, PPV and NPV for thyroid cancer for different ultrasound patterns (including RTE and ARFI) in thyroid nodules.
Table 3.
ARFI velocity characteristics.
Figure 3.
Receiver-operating characteristic (ROC) curves for ARFI-imaging of thyroid nodule (ARFI-nod) and for the ratio of ARFI-imaging of thyroid nodule divided by ARFI-imaging of healthy thyroid tissue (ARFI-rat) for diagnosis of malignant thyroid nodules (AUROC 69% and 71%, respectively) and the ROC curves for the combination of these criteria with Realtime Elastography Score (ES) 3–4 (AUROC 78% and 78%, respectively).
The improvements with respect to ARFI alone were not significant (p = 0.18 for ARFI-nod, p>0.20 for ARFI-rat), analogously the improvements with respect to ES alone were not significant (p>0.20 in both cases).