Successful Tc-99m MIBI imaging of recurrent hyperparathyroidism in parathyroid autotransplanted patients

Use of digirad 2020tc Imager, a multi-crystal scintillation camera with solid-state detectors in one case for the imaging of autografts of parathyroid glands

99mTc-methoxy-isobutyl-isonitrile (99mTc-MIBI) scintigraphy with Digirad 2020tc ImagerTM (2020tc), which was a multi-crystal scintillation camera with solid-state detectors was performed for patients with secondary hyperparathyroidism having autografts of parathyroid glands in the right arm. With the 2020tc camera, three abnormal accumulations were found in the right arm. The images obtained with this camera were superior in resolution to those obtained with a conventional NaI crystal gamma camera (ZLC7500, Siemens, Germany). The next day, resection of autografts of parathyroid glands was done. Four hyperplastic parathyroid glands were resected and all were hyperplastic in pathological findings.

Parathyroid imaging with technetium-99m sestamibi

The accurate identification of the location of hyperfunctioning parathyroid nodules is essential to the effective surgical treatment of hyperparathyroidism. Radionuclide imaging has played an important role in the detection of pathological parathyroid nodules. Sestamibi is a new radiopharmaceutical with a good affinity for parathyroid tissue that images hyperfunctioning parathyroid lesions as hot nodules. The double-phase protocol with early (ten minutes) and delayed (120 minutes) imaging is effective fordetecting the parathyroid lesions. The use of a pinhole collimator improves the sensitivity, but attention should be paid to the ectopic gland. Most lesions heavier than 250 mg could be detected with this scintigraphy, but the detectability of hyperplastic glands is inferior to that of adenomas. A sestamibi scan is better for the detection of ectopic lesions and recurrent disease than ultrasonography, and its detectability is also superior to other radionuclide tests such as tetrofosimin scanning and the subtraction technique using thallium-201 and Tc-99m pertechnetate images. The application of sestamibi to radionuclide-guided parathyroidectomy has been studied with encouraging results. Sestamibi can also be used for the evaluation of autotransplanted glands.

Recurrent hyperfunctioning parathyroid gland demonstrated on radionuclide imaging and an intraoperative gamma probe

Radionuclide imaging with Tc-99m MIBI is the preferred mode of parathyroid localization in current practice. It also successfully identifies hyperfunctioning autotransplanted parathyroid tissue. The authors report a case with recurrent hyperparathyroidism after total parathyroidectomy and autotransplantation in the forearm. Double-phase Tc-99m MIBI imaging successfully localized the hyperfunctioning parathyroid tissue, which was missed by magnetic resonance imaging and ultrasonography. In addition, the parathyroid tissue was localized using an intraoperative probe at subsequent surgery.