Comparison between thallium-technetium subtraction scan and other imaging modalities in the preoperative localization of abnormal parathyroid glands.

A total of 15 patients who underwent total neck exploration for hyperparathyroidism were studied with four different imaging modalities: (a) Tl-201/Tc-99m subtraction scan (SS), (b) ultrasonography (US), (c) computed tomography (CT) and (d) magnetic resonance imaging (MRI). Accuracy for locating enlarged parathyroid(s) was 60.0% by SS, 60.0% by US, 33.3% by CT and 71.4% by MRI. Our results suggested that at present none of the imaging modalities was adequate on its own to locate all enlarged parathyroid gland(s) in patients with hyperparathyroidism.