Radionuclide scanning in parathyroid diseases.

BACKGROUND: New radionuclide agents and scanning procedures have markedly improved preoperative parathyroid gland localization. The aim of this review was to evaluate the results of parathyroid scanning and to clarify its current place in the clinical management of parathyroid diseases.

METHODS: The literature describing the different radioisotopes and available scanning techniques was analysed and their clinical outcome in various parathyroid diseases was evaluated.

RESULTS: Using 99mTc-radiolabelled sestamibi or other 9mTc-labelled cationic complexes, parathyroid scintigraphy detects 87 per cent of solitary adenomas (n=894), 55 per cent of abnormal glands in patients with multiglandular disease (n=303) and 75 per cent of persistent or recurrent lesions in patients with previous neck surgery (n=240). If necessary, three-dimensional imaging techniques can clarify the spatial localization of an ectopic uptake focus. The positive predictive value of the available scanning procedures is over 95 per cent, but false-positive uptake may be encountered.

CONCLUSION: Radionuclide parathyroid gland scanning with 99mTc-labelled cationic complexes is the initial non-invasive method of choice for preoperative parathyroid gland localization in patients at special risk and/or with previous neck exploration. While scanning has also been proposed to facilitate parathyroidectomy, there is no objective evidence to support its routine use before a first-time surgical procedure.