The role of radionuclide diagnostics in the algorithm of complex preoperative topical visualization of parathyroid glands in patients with concomitant thyroid diseases

Aims: Comparison of the effectiveness of instrumental diagnostic methods in patients with primary hyperparathyroidism and concomitant thyroid pathologies and optimization of the algorithm for complex preoperative topical visualization. Materials and methods: The results of preoperative topical diagnostics in patients with PHPT (n=150) were analyzed in groups without concomitant thyroid pathology, with autoimmune thyroid disease, and with nodule. All patients underwent ultrasound examination, planar scintigraphy, and single-photon emission computed tomography combined with X-ray computed tomography. In each group, the diagnostic sensitivity and positive predictive value were assessed for all diagnostic methods and combinations of imaging methods. During the comparative analysis of patients, the main features influencing the detectability of parathyroid gland formations in radionuclide diagnostics were identified. Based on the obtained results, an algorithm for topical diagnostics of parathyroid formations was developed taking into account the influence of thyroid pathology. Results: In case of nodular (multinodular) goiter, the most effective imaging methods are SPECT/CT (DC 85%) and a combination of ultrasound + SPECT/CT (DC 88%). In patients with autoimmune thyroid diseases (ATD), the most informative is CT with contrast enhancement (DC 79%), and among combinations of ultrasound + CT with contrast enhancement (DC 85%). Factors influencing the effectiveness of radionuclide diagnostics of the parathyroid gland are: the functional and structural state of the thyroid gland (hypo-/hyperthyroidism, as a manifestation of AID, nodules), volume, vascularization and density of the thyroid gland. Conclusions: SPECT/CT is the most informative diagnostic method in patients with concomitant nodular thyroid pathology. In patients with PHPT and concomitant AID of the thyroid gland, contrast-enhanced computed tomography demonstrates higher efficiency compared to scintigraphy and SPECT/CT. The use of the algorithm of complex topical diagnostics taking into account the influence of thyroid pathology allows to reduce the number of additional studies and reduces financial costs.