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Computed tomography of the parathyroids: The value of density measurements to distinguish between parathyroid adenomas of the lymph nodes and the thyroid parenchyma

Research output: Contribution to journalArticleScientificpeer-review


Original languageEnglish
Pages (from-to)597-603
Number of pages7
JournalDiagnostic and interventional imaging
Issue number7-8
Publication statusPublished - 2012
Publication typeA1 Journal article-refereed


Purpose: To compare the densities of parathyroid adenomas, lymph nodes and the thyroid parenchyma during multi-phase cervico-thoracic computed tomography to determine the differentiating threshold values. Materials and methods: This study comprises 30 patients operated for a parathyroid adenoma after computed tomography without injection and then 45 and 70 seconds after the injection of an iodine based contrast product (350 mgI/mL, 150 mL, 3 mL/s). The density of the adenomas, lymph nodes and thyroid was measured during the three phases (D0, D45, D70). The relative enhancement (RE) at 45 seconds was calculated: RE = (D45-D0)/D0. Results: A significant difference was found in the spontaneous density of the parathyroid adenomas of the thyroid (P <0.01) with a threshold value of 75 HU. A significant difference is found in the enhancement after injection of the adenomas and lymph nodes (P <0.01). The adenomas present an enhancement peak at 45 seconds while the maximum enhancement of the lymph nodes is at 70 seconds. At 45 seconds, a threshold value of 114 HU and an RE 125% allows them to be distinguished (sensitivity and specificity 0.96). Conclusion: Measurement of the densities can differentiate between the parathyroid adenomas, lymph nodes and thyroid.


  • 4D computed tomography, Computed tomography, Hyperparathyroidism, Parathyroid glands, Parathyroid tumours