ABSTRACT

APPEARANCE The four normal parathyroid glands are generally located at the poles of the thyroid lobes, although the inferior parathyroid glands may be ectopic, found in the upper mediastinum. Occasionally, the normal parathyroid gland can be identied separate from thyroid tissue, especially in a longitudinal view. A linear high-re‚ective band representing an aponeurosis or a brous sheath may surround the gland. The normal parathyroid gland may either be seen as a slightly low-re‚ective or slightly high-re‚ective oval area adjacent to the normal thyroid. A parathyroid adenoma is identied as an oval-shaped, low-re‚ective area, with increased color Doppler ‚ow, in the expected location of a parathyroid gland.