Tc 99 Sestamibi scan 30 min after injection. Here the thyroid gland takes up the isotope. The parathyroids are not visible.
AP projection Tc 99 Sestamibi scan 2 hours after injection. The isotope washes off from the thyroid and concentrates in the parathyroid, but the signal is faint. (A yellow circle shows the signal)
Left Oblique projection Tc 99 Sestamibi scan 2 1/2 hours after injection. Sometimes, the oblique view shows the signal better than the AP projection.
This right inferior parathyroid adenoma "lights up" 15 minutes after Tc injection and remains "hot" two hours later. The picture on the right shows the removed parathyroid adenoma (2.5 x 1.2 cm).
This left inferior parathyroid adenoma was found exactly where the sestamibi scan indicated, in the angle between the left thyroid lobe and the left clavicle. Methylene blue is taken up by the adenoma, making it readily visible against the yellow and brown background colors of the thyroid gland and adjacent tissues of the paratracheal "gutter".
This adenoma is in the right mediastinum. It was localized with a Sestamibi scan and removed . The right picture below is a magnification of the actual incision and the arrow points superiorly, for orientation.
This very large parathyroid turned out to be a parathyroid cyst (parathyroid cystic adenoma).