Parathyroid adenoma screening efficacies of different imaging tools and factors affecting the success rates

We aimed to compare the efficacy of three different parathyroid adenoma screening tools--high-resolution ultrasonography (USG), technetium Tc 99m-methoxyisobutylisonitrile (MIBI) parathyroid scintigraphy, and magnetic resonance imaging (MRI)--and we evaluated the factors affecting the detection success rates.

Parathyroid imaging was evaluated by USG, double-phase 99mTc-MIBI parathyroid scintigraphy, and cervical MRI in patients with hyperparathyroidism (n=39).

Among the 39 patients, USG, parathyroid scintigraphy, and MRI correctly identified 35 adenomas (89.7%), 28 adenomas (71.8%), and 26 adenomas (66.7%), respectively. Positive predictive values for USG (34/35), scintigraphy (27/28), and cervical MR (26/26) imaging were 97.1%, 96%, and 100%, respectively. Parathyroid adenomas were detected with 92.3% (36/39) certainty when both USG and scintigraphy modalities were applied together. Minimally invasive parathyroidectomy under local anesthesia with unilateral incision was successfully performed in 24 (61.5%) patients.

Minimally invasive surgery for parathyroid adenomas has been developed and has equal success with traditional surgery. However, accurate localization of adenomas should be obtained prior to surgery. In this study, ultrasound was found to be effective in localizing adenomas for successful surgery. Adding other imaging modalities does not improve localizing the parathyroid adenomas.