Objectives Pre- and intraoperative diagnostic tools influence the surgical management of primary hyperparathyroidism (PHPT), whereby their performance of classification varies considerably for the two common causes of PHPT: solitary adenomas and multiglandular disease. A consensus on the use of such diagnostic tools for optimal perioperative management of all PHPT patients has not been reached. Design A decision tree model was constructed to estimate and compare the clinical outcomes and the cost-effectiveness of preoperative imaging modalities and intraoperative parathyroid hormone (ioPTH) monitoring criteria in a 14-year time horizon. The robustness of the model was assessed by conducting a one-way sensitivity analysis and probabilistic uncertainty analysis. Setting The United States healthcare system. Population A hypothetical population consisting of 5,000 patients with sporadic, symptomatic, or asymptomatic PHPT. Interventions Pre- and intraoperative diagnostic modalities for parathyroidectomy. Main outcome measures Costs, quality-adjusted life years (QALYs), net monetary benefits (NMB), clinical outcomes. Results In the base-case analysis, four-dimensional (4D)-computed tomography (CT) was the least expensive strategy with $10,289 and 13.93 QALYs. Ultrasound and 99mTc-Sestamibi single-photon-emission computed tomography/CT were both dominated strategies, while 18F-fluorocholine positron emission tomography was cost-effective with a net monetary benefit of $264 considering a willingness to pay threshold of $95,958. The application of ioPTH monitoring with the Vienna criterion decreased the rate of reoperations from 10.50 to 0.58 per 1,000 patients. Due to an increased rate of bilateral neck explorations from 257.45 to 347.45 per 1,000 patients, it was not cost-effective. Conclusions 4D-CT is the most cost-effective instrument for the preoperative localization of parathyroid adenomas. Due to an excessive increase of bilateral neck explorations, the use of ioPTH monitoring is not cost-effective in PHPT but leads to a significant reduction of reoperations.

The authors have declared no competing interest.

This study was funded by the 'Ruth & Arthur Scherbarth Stiftung'.

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