Preoperative localization of parathyroid glands in secondary hyperparathyroidism and concomitant thyroid disease

Hippokratia 2000, 4(1):19-25

N Sikas, D Gakis, D Takoudas, G Vergoulas, I Fouzas, N Karatzas, A Antoniadis


Abstract

99m?Tc-sestamibi and ultrasound are the most commonly used methods for the preoperative localization of parathyroids in patients with secondary hyperparathyroidism. The aim of this study was to assess the value and usefulness of parathyroid preoperative localization in secondary hyperparathyroidism, in the presence of coexistent thyroid disease. Between 1996 and 1998, seventy two 72 parathyroidectomies for secondary hyperparathyroidism were performed. In 10 patients we found concomitant thyroid disease (14%). For the preoperative localization we used ultrasound and 99m?Tc-sestamibi scan.Ultrasound revealed 19 parathyroid glands (50%) out of the 38 that were surgically removed.Their mean weight was 0.738 gr vs. 0.438 gr of those not detected (p=0.21) and the mean size was 1.221 cm vs. 0.973 cm (p=0.21) respectively. 99m?Tc-sestamibi demonstrated 17 glands (45%) with a mean weight of 0.836 gr vs. 0.387 gr of the glands not demonstrated (p<0.05) and a mean size of 1.294 cm vs. 0.938 cm (p<0.05) respectively. Two glands were not found. Only 10 parathyroid glands (26.3%) were identified simultaneously by both ultrasound and 99m?csestamibi (mean size 1.38 cm and mean weight 0.991 gr). Ultrasound demonstrated the superimposed thyroid disease in all 10 patients (100%), while 99m?c-sestamibi only in 3 (33%). The histology of the parathyroids was predominantly nodular hyperplasia in those glands detected with 99m?Tc-sestamibi. Nodular goiter was the predominant lesion of the thyroid gland. Both studies, when they are used alone, have shown relatively low sensitivity (45% with 99m?Tc sestamibi and 50% with ultrasound) in detecting parathyroid glands in secondary hyperparathyroidism and concomitant thyroid disease. Ultrasound scan can give information for the thyroid disease and it can be the first and sometimes the only study in every patient with secondary hyperparathyroidism undergoing neck exploration for a first time.