Sonographic characteristics of parathyroid adenomas

Ultrasound views of parathyroid adenomas.
(A) Sagittal image of the upper pole of the right lobe of the thyroid gland, demonstrating a hypoechoic parathyroid adenoma posterior to the thyroid parenchyma.
(B) Sagittal image of the lower pole of the lower pole of the left lobe of the thyroid gland with an adjacent hypoechoic parathyroid adenoma measuring 9 mm in greatest dimension.