Dual Tracer Imaging for Localization of Parathyroid Lesions

During the period from July 1983 through October 1984, a group of 38 patients with elevated serum calcium, parathormone (PTH) and/or clinical suspicion of hyperparathyroidism were studied by TI-201 Tc-99m dual tracer parathyroid imaging (DTPI). Seventeen of 18 parathyroid lesions were identified correctly. There was one false-negative, and the size of the adenoma missed by DTPI was less than 1.0 cm in diameter (1.0 × 0.5 × 0.2). There was one true-negative case. The other fifteen with negative scans are being followed clinically. Because of the small population studied, statistical analysis was not ascertained. However, this simple, noninvasive procedure has become a very useful diagnostic tool for the detection and localization of parathyroid lesions causing hyperparathyroidism, and the DTPI should be used in conjunction with ultrasonography and CT scanning in the preoperative evaluation in primary and secondary hyperparathyroidism.