Preoperative ultrasound in patients undergoing initial neck exploration for primary hyperparathyroidism

92 patients with primary hyperparathyroidism were subjected prospectively to preoperative ultrasound to identify enlarged parathyroid glands and detect simultaneous thyroid lesions of surgical significance. The overall sensitivity and specificity rates were 62.7% and 95.7%, 85.2% and 96.8% for patients with a single adenoma, 44.3% and 88% for those with multiglandular disease, 56.8% and 95.6% for those with simultaneous thyroid disease and 20% and 100% for mediastinal glands. Ultrasound revealed a pathological thyroid gland in 26 patients (28%). The sensitivity and specificity rates were 96% and 100%. The thyroid lesion was considered clinically significant in 15 of the 92 patients (16.3%) and only in three patients (3.3%) was the diagnosis not established preoperatively. Operating room times and costs were significantly lower for patients with an accurate ultrasound scan than for those with an inaccurate scan (P < 0.001). We conclude that both the sensitivity of ultrasound for locating enlarged parathyroid glands and its yield of previously unknown thyroid lesions of surgical significance are too low to warrant preoperative ultrasound evaluation. Although our operating room expenses were significantly higher for patients with an inaccurate scan, the cost effectiveness of preoperative ultrasound cannot be proved until a prospective, randomised investigation has been carried out.