ABSTRACT
In a series of 45 patients operated upon for primary hyperparathyroidism, a total of 167 parathyroid glands were confirmed. Thirty out of the 43 parathyroid masses potentially accessible to ultrasounds were correctly identified by preoperative cervical ultrasonography. There were 124 true negative results, including one retro-oesophageal mass and one mediastinal mass, 1 false-positive result and 11 false-negative results, giving the method a sensitivity of 73% and a specificity of 99%. Sensitivity increases with the experience of the operator. The main factors that reduce sensitivity are change of apparatus, old age of the patient, small masses (less than 500 mg) and coexistence of a thyroid disease (22% of the cases). The ease with which parathyroid masses can be correctly identified is independent from plasma calcium and parathyroid hormone values.
