Fig. 20
From: Neoplastic pathology at the crossroads between neck imaging and cardiothoracic imaging
Parathyroid Adenoma. a Grayscale with Doppler ultrasound image demonstrates an ovoid well-circumscribed hypoechoic lesion containing cystic anechoic areas, located at the inferior posterior aspect of the left thyroid lobe. Doppler shows the vessels feeding the adenoma. b Tc99 sestamibi scan demonstrates increased radiotracer uptake in the lower pole of the right thyroid lobe in a companion case with persistent uptake 2 h later (arrows). Multiphasic 4-dimensional CT imaging of the parathyroid glands was performed in the same patient as the nuclear medicine study. c Axial precontrast (left), arterial phase (middle), and late arterial/delayed phase (right) images identified two enhancing nodules in the posterior aspect of the right lower thyroid lobe which washed out on delayed phase imaging (upper nodule shown). This nodule measured 83 HU precontrast (white arrow), 175 HU on arterial phase (blue arrow), and 115 HU on delayed phase (orange arrow). d 3D reconstructions created from the CT imaging demonstrate the position of the two nodules (yellow and turquoise) relative to the thyroid gland (purple) on the posterior view, assisting in surgical pre-procedure planning