Abstract: Objective To compare double phase ^99mTc-MIBI imaging with ultra-sound,CT and MRI in the diagnosis of hyperparathyroidism.Methods Sixty-five patients with clinical diagnosis of hyperparathyroidism were injected intravenously with 370 MBq(10 mCi) of ^99mTc-MIBI,and imaged 15 min later as early phase imaging and 120 min later as delayed phase imaging respectively.All patients under went B ultra-sound examination;20 and 11 patients underwent CT and MRI,respectively.Results Thirty-six cases among 65 patients showed high level of parathyroid homone(PTH),which was considered as diagnostic criterion for hyperparathyroidism.Among these,34 showed positive radionuclide parathyroid images,with the sensitivity,specificity and accuracy of 94.4%,100% and 96.9%,respectively.Thirty-two patients showed abnormal ultra-sound results,and the sensitivity,specificity and accuracy were 88.9%,93.1% and 90.8%,respectively.Seventeen CT images and 8 MR images showed positive results,respectively.Thirty-five adenomas and 1 histo-pathologically proved hyperplastic gland were removed from 34 patients.Conclusion Double phase ^99mTc-MIBI imaging is a kind of useful and reliable approach for localization of parathyroid adenomas.Combined with other examinations,double phase ^99mTc-MIBI imaging can improve the accuracy of diagnosis of the parathyroid lesions before surgery.

Key words: hyperparathyroidism, radionuclide imaging, ultra-sound, computed tomography