Abstract
Parathyroid cyst is a rare clinical entity and often presents as a diagnostic challenge,
especially when presents in conjunction with a coexistent parathyroid adenoma. Patient
with primary hyperparathyroidism had presented with a localised left inferior parathyroid
adenoma with a coexistent right inferior parathyroid cyst which was initially missed
on routine ultrasound and sestamibi scan. Suspicion of right inferior thyroid cyst
was raised on ultrasound done by a dedicated parathyroid ultrasonologist. Right inferior
thyroid cyst was confirmed to be parathyroid cyst on histopathological examination.
Parathyroid cysts are seldom picked on sestamibi due to compressed parathyroid tissue
present only at the periphery of the cyst. Hence, use of adjunct anatomical imaging
like ultrasound, CT scan or MRI is worthwhile to reduce chances of missing hyperfunctional
parathyroid tissue, which can eventually lead to revision surgery for persistent primary
hyperparathyroidism.
Keywords
Parathyroid adenoma - parathyroid cyst - sestamibi - ultrasound