A Novel Ultrasound-based Nomogram Using Contrast-enhanced and Conventional Ultrasound Features to Improve Preoperative Diagnosis of Parathyroid Adenomas versus Cervical Lymph Nodes.

Introduction: Precise preoperative localization of parathyroid gland lesion is essential for guiding surgery in primary hyperparathyroidism (PHPT). The aim of our study was to investigate the contrast-enhanced ultrasound (CEUS) characteristics of parathyroid gland adenoma (PGA) and to evaluate whether PGA can be differentiated from central cervical lymph nodes (CCLN).

Methods: Fifty-four consecutive patients with PHPT were retrospectively enrolled and underwent preoperative imaging with high-resolution ultrasound (US) and CEUS, and underwent subsequent parathyroidectomy. One hundred and seventy-four lymph nodes of papillary thyroid carcinomas (PTC) patients were examined by high-resolution US and CEUS, and underwent unilateral, subtotal, or total thyroidectomy with central neck dissection were enrolled. By incorporating US and CEUS characteristics, a predictive model presented as a nomogram was developed, and their performance and utility were evaluated by plotting receiver operating characteristic (ROC) curves, calibration curves and decision curve analysis (DCA).

Results: Three US characteristics and two CEUS characteristics were independent characteristics related to PGA for their differentiation from CCLN, and were obtained for machine learning model construction. The area under the receiver characteristic curve (AUC) of the US+CEUS model was 0.915, was higher than the other US model (0.874) and CEUS model (0.791).

Conclusion: It is recommended that CEUS techniques be used to enhance the diagnostic utility of US in cases of suspected parathyroid lesions.

Advances in knowledge: This is the first study to use a combination of US+CEUS to build a nomogram to distinguish between PGA and CCLN, filling a gap in the existing literatures.