Dynamic 4 dimensional contrast enhanced MRI for localization in primary hyperparathyroidism.

Purpose: It can be challenging to localize the lesions in certain cases of primary hyperparathyroidism. Recently, it has been proposed that assessing the localization of parathyroid lesions with dynamic images enhances the diagnostic power of standard MRI (magnetic resonance imaging) due to the hypervascular structure of these lesions. In this study, we aimed to evaluate the success of four-dimensional dynamic perfusion MRI (4D MRI) in localizing parathyroid lesions.

Methods: Thirty patients who underwent 4-dimensional dynamic MRI diagnosed with primary hyperparathyroidism and indications for surgery, whose USG (ultrasonography) and/or Tc 99m sestamibi SPECT scan were negative or discordant, were included. The sensitivity and positive predictive values (PPV) were calculated for each imaging modality.

Results: Of the 30 patients, 29 had parathyroid adenoma, and one had parathyroid hyperplasia in histopathologic examination. 4D MRI accurately identified the location of parathyroid lesions in 25 of 30 patients (sensitivity 83.3%, PPV 96.1%), whereas USG successfully identified the lesion location in 21 patients (sensitivity 70%, PPV 91.3%) and Tc 99m sestamibi SPECT scan in 17 patients (sensitivity 56.7%, PPV 94.4%). The sensitivity of the combination of three imaging modalities was found to be 96.7%.

Conclusion: 4D MRI can be utilized as a complementary imaging modality to localize parathyroid lesions, offering the advantage of no ionizing radiation, especially when USG and/or Tc 99m sestamibi SPECT scans cannot reliably identify them.