A 55-year-old woman with primary hyperparathyroidism (calcium 11.5 mg/dL, PTH 95 pg/mL) has a negative sestamibi scan and equivocal neck ultrasound. Which imaging modality has the highest sensitivity for localizing parathyroid adenomas in this setting?
- A MRI neck with contrast
- B Four-dimensional CT (4D-CT) of the neck and mediastinum ✓
- C PET-CT with 18F-FDG
- D Thallium-technetium subtraction scintigraphy
Correct answer: B. Four-dimensional CT (4D-CT) of the neck and mediastinum
Explanation
4D-CT (multiphasic computed tomography) has the highest sensitivity (approximately 85 to 90 percent) for localizing parathyroid adenomas when sestamibi and ultrasound are negative or discordant. It provides anatomical detail combined with perfusion characteristics. MRI has lower sensitivity. PET-CT is not first-line for parathyroid localization. Thallium-technetium subtraction scintigraphy is largely obsolete and has been replaced by sestamibi SPECT/CT.
Reference: Schwartz's Principles of Surgery, 11th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.