[Persistent or recurrent hyperparathyroidism in periodically hemodialyzed patients. Value of preoperative cervical ultrasonography. 6 cases].

In 2 cases of recurrent secondary hyperparathyroidism and 4 cases of persisting secondary hyperparathyroidism observed in patients treated by chronic haemodialysis, 8 hyperplastic parathyroid masses and 1 parathyroid adenoma, all located in the lower part of the neck, were removed after percutaneous ultrasonographic detection. There were 7 true positive and 1 unexplained false positive results. In 1 out of the 2 false negative results, the mass located behind the esophagus could not be detected because of the laryngotracheal gas. Two masses located inside the thyroid gland and a 5th hyperplastic gland were correctly identified by ultrasound. Two reluctant patients accepted a new cervicotomy because of the ultrasound reports. The reports played a prominent role in the operative technique in 3 cases.