Key Points

• Understanding the embryologic origins of the superior and inferior parathyroids helps guide exploration, particularly when seeking undiscovered or ectopic glands.
• Mediastinal parathyroids can be found in 11% to 22% of patients, but only 2% to 4% require sternotomy for removal. Most can be removed via a cervical approach.
• Imaging studies are indicated for any question of mediastinal or intrathoracic parathyroids:^99mTc-sestamibi and new 4-D computed tomography (CT) are most commonly employed.
• Intraoperative parathyroid hormone monitoring is now a critical adjunct in the surgical treatment of parathyroid disease and can limit the extent of surgery.
• Never discard normal parathyroid tissue, and always treat any parathyroid tissue discovered during reoperations as the patient’s only remaining tissue.
• Hyperparathyroidism, considering all cases, is cured by surgery 95% to 99% of the time, including 90% of reoperations and 95% of reoperations with successful localization.