Visualizing hyperparathyroidism: A pictorial essay of Tc-99m MIBI parathyroid imaging across different etiologies

Parathyroid scintigraphy is an imaging technique that uses gamma-emitting radionuclide to locate hyperfunctioning parathyroid glands in patients with hyperparathyroidism. It is valuable for preoperative assessment before parathyroidectomy, which is a curative surgery in most cases of primary hyperparathyroidism and some cases of secondary hyperparathyroidism. There are several different techniques for parathyroid scintigraphy. In general, the scintigraphy is performed with Tc-99m MIBI, a mitochondria-targeting radiotracer. Some techniques also supply the Tc-99m MIBI scintigraphy with thyroid scintigraphy to differentiate between thyroid and parathyroid tissue. Parathyroid scintigraphy can detect primary hyperparathyroidism with a sensitivity of 80% and a specificity of 84%. It can also detect secondary hyperparathyroidism with a sensitivity of 58% and a specificity of 93%. The unique advantage of parathyroid scintigraphy is the ability to identify supernumerary and ectopic parathyroid abnormalities, which can significantly affect surgical planning and outcomes.