This case serves to demonstrate the typical ultrasound appearance of a parathyroid adenoma - a rounded, slightly hypoechoic lesion with increased vascularity. However, ultrasound characteristics may vary considerably.
Tc99m-sestamibi scans are often used in combination with ultrasound, either to verify that a lesion detected with ultrasound indeed is a parathyroid adenoma, or to increase diagnostic accuracy in cases of a negative ultrasound. This often provides important information to the surgeon, especially in patients with ectopic parathyroid glands in locations inaccessible by ultrasound.
It is important to recognize the diagnostic overlap of these two methods, the combination of which offers a preoperative diagnostic sensitivity of 95% and specificity of 91% according to one study 2.