Sestamibi/iodine subtraction single photon emission computed tomography inreoperative secondary hyperparathyroidism

Background. Sestamibi/iodine subtraction single photon emission computed to mography (SPECT) has been used successfully for the preoperative localizati on of adenomatous and hyperplastic parathyroid tissue in primary hyperparat hyroidism, but the clinical usefulness of this technique in secondary hyper parathyroidism remains uncertain. The purpose of this stud was to evaluate parathyroid localization that uses sestamibi/iodine subtraction SPECT in pa tients with secondary hyperparathyroidism before reoperative parathyroid su rgery. Methods. Fourteen consecutive patients wit chronic renal failure and second ary hyperparathyroidism who had previously undergone total parathyroidectom y combined with parathyroid autotransplantation in a sternocleidomastoid mu scle were studied. Before reoperation,each patient received 400 mu Ci of so dium iodide I 123 orally and 20 to 25 mCi of technetium Tc 99m (Tc-99m)-ses tamibi intravenously, followed by sestamibi/iodine subtraction SPECT of the neck and chest At surgery, the location, weight, and histopathologic resul ts of all identified parathyroid tissue were recorded. Results. At surgery, 1 hyperplastic parathyroid gland was resected from eac h of 13 patients including 1 undescended gland, 6 parathyroid autotransplan ts, and 5 mediastinal glands. The mean weight of the resected parathyroid g lands was 1707 mg (range, 85-5300 mg). Sestamibi/iodine subtraction SPECT c orrectly identified and localized all 13 parathyroid glands (100% sensitivi ty) and was negative in the 1 patient whose surgery was unsuccessful. Conclusions. The Tc-99m-seatamibi/I-123 subtraction SPECT is able to correc tly localize hyperplastic parathyroid tissue in patients with secondary hyp erparathyroidism who have previously undergone parathyroid surgery an dis a clinically useful study before reoperation.