Department of Endocrine Surgery, Toranomon Hospital
Ultrasonography, Primary hyperparathyroidism, Localization study
Between 1987 and 1990, 46 patients with primary hyperparathyroidism were examined preoperatively using 7.5 MHz linear-array real-time ultrasonography. Of the 46 patients in this series, 45 had a single adenoma and one had double adenomas.
Ultrasonography correctly identified 39 of the 47 parathyroid adenomas. Of the six adenomas not identified by ultrasonography, three were associated with thymic tissue in the lower neck and one was located behind the carotid artery. Two large parathyroid adenomas that had multiple internal cystic components were detected by ultrasonography, but were misdiagnosed as cystic thyroid adenomas. The three false-positive results were due to one enlarged lymph node and two protuberant thyroid nodules.
When considering that each patient has four parathyroid glands, a sensitivity of 83%, a specificity of 98%, and an accuracy of 94% were achieved.
We analyzed the relationship between the result of ultrasonographic localization study and adenoma weight, the relationship between the result of ultrasonographic localization study and adenoma location, and the relationship between the result of ultrasonographic localization study and coexistence with thyroid nodules. It was found that adenomas located separately from the thyroid were difficult to identify by ultrasonography(p=0.0005).