Background: The aim of this study was to evaluate the diagnostic efficacy of 18 F-fluorocholine ( 18 F-FCH) PET/CT for uremic hyperparathyroidism (uHPT) compared to 99m Tc-sestaMIBI SPECT/CT and ultrasonography (US). Methods: A total of 17 uHPT patients with stage 5 chronic kidney disease (CKD) were prospectively enrolled. All patients underwent US, 99m Tc-sestaMIBI SPECT/CT, and 18 F-FCH within 2 months and received surgical treatment. Visual and quantitative methods were used for image analyses. Intraoperative localization and postoperative histological results of the reference standard as well as the sensitivity, specificity, accuracy, positive predictive value (PPV), and negative predictive value (NPV) of the three modalities were analyzed using Pearson's χ 2 tests. In addition, the diagnostic efficacy of 18 F-FCH PET/CT for uHPT was evaluated. The relationships between PET parameters and laboratory parameters were assessed using the Spearman correlation coefficient.Results: A total of 63 parathyroid hyperplasia lesions were resected in 17 uHPT patients, and 53 lesions were detected using 18 F-FCH PET/CT with no false-positive results. The sensitivity, specificity, accuracy, PPV, and NPV were 84.13%, 100%, 86.49%, 100%, and 52.38%, respectively. In comparison, the corresponding values for 99m Tc-sestaMIBI SPECT/CT and US were 63.49%, 90.91%, 67.57%, 97.56%, and 30.30% and 61.90%, 81.82%, 64.86%, 95.12%, and 27.27%, respectively. The volume of hyper-functioning parathyroid glands was significantly different between lesions positive in 18 F-FCH PET/CT and negative in 18 F-FCH PET/CT (mean volume 1.36 ± 0.55 cm 3 vs. 0.83 ± 0.26 cm 3 ; P = 0.019). US misidentified intrathyroidal parathyroid hyperplasia as thyroid nodules in three patients, while 18 F-FCH PET correctly identified the anatomy. No significant associations were observed between PET parameters and laboratory parameters in uHPT.Conclusion: 18 F-FCH PET/CT was more sensitive and accurate for uHPT than 99m Tc-sestaMIBI SPECT/CT and US, and had better preoperative diagnostic efficacy, particularly for lesions diagnosed as a thyroid nodule by US.

ObjectiveWe evaluated the difference in parathyroid visualization on 18F-FCH PET/CT images obtained at 5 and 60 min, and quantitatively analyzed the mode of FCH uptake at different time points, to determine the best imaging time for FCH PET/CT.MethodsThis retrospective study included 73 patients with hyperparathyroidism (HPT) who underwent 18F-FCH PET/CT imaging between December 2017 and December 2021. The diagnostic efficiency of 5- and 60-min dual time point imaging for the diagnosis of hyperparathyroidism and parathyroid adenoma and hyperplasia, were compared using visual and quantitative analyses.ResultsDual-time 18F-FCH PET/CT imaging visual analysis had diagnostic value for HPT. The receiver operating characteristic curve of PET/CT quantitative parameters for the diagnosis of HPT and lesions showed that the parathyroid/thyroid SUVmax ratio for 60-min imaging had a higher sensitivity and specificity (based on patient, sensitivity: 90.90% and specificity: 85.71%; based on focus, sensitivity: 83.06% and specificity: 85.71%) compared to that for 5-min imaging. PET/CT quantitative parameters can distinguish parathyroid adenoma and hyperplasia. The 60-min parathyroid SUVmax value had the highest diagnostic value (cutoff: 3.945; area under the curve: 0.783).ConclusionThe quantitative parameters of 60min 18F-FCH PET/CT have more advantages in aiding in the pathologica diagnosis and clinical treatment of HPT.