Primary hyperparathyroidism: can ultrasonography be the only preoperative diagnostic procedure?

Purpose. The purpose of our study was to assess the role of ultrasonography (US) before surgical treatment of primary hyperparathyroidism. Materials and methods. We retrospectively evaluated 77 patients (60 women, 17 men; mean age 59 years) with primary hyperparathyroidism who underwent parathyroid US prior to surgery. Sixty-five of 77 (84%) patients had undergone Tc-99m- sestamibi (MIBI) scintigraphy. The results were correlated with the surgical and histopathological findings. Results. Surgery revealed 85 abnormal parathyroid glands in 77 patients (70 adenomas, 15 hyperplasias). The locations of the parathyroid glands were typical cervical (n=77), thyrothymic ligament (n=3), carotid sheath (n=2), and mediastinum (n=3). In two patients, intrathyroid microadenoma was diagnosed by histopathology. Seventy-four enlarged glands in 64 patients were correctly identified at US. Per-patient sensitivity and positive predictive values, respectively, were 84% (64/76) and 99% (64/65) for US, 68% (44/65) and 100% (44/44) for scintigraphy and 91% (59/65) and 98% (59/60) for both techniques combined. We weighed 63 out of 85 glands, obtaining a value of 1,004 1,564 mg; 460 mg (mean standard deviation; median). Conclusions. Preoperative detection and localisation of enlarged parathyroid glands can be based on US, an inexpensive and widely available method, limiting the use of scintigraphy to those cases with negative and/or doubtful findings on US.