The Impact of Iodinated Contrast Media Used in Epidural Steroid Injections on Thyroid Function Tests

Abstract Objective The use of iodinated contrast media (ICM) inevitably increases in conjunction with the growing number of epidural steroid injections (ESI) administrations. The purpose of this study was to investigate the relationship between thyroid functions and ICM exposure through ESI procedures. Design: Prospective, observational study. Setting: A university hospital pain management center. Methods This study was conducted between June 2022 and February 2023. Participants between the ages of 18 and 65 who had received an epidural steroid injection at our outpatient pain clinic comprised the study's population. Thyroid function tests (fT3, fT4, and TSH) were measured before and 3 weeks after the procedure. Results A total of 124 participants (80 women and 44 men) were analysed. The average amount of contrast media administered was 1.34 ml. A significant increase was observed only in the fT4 value compared to pre-procedure (p = 0.017), and thyroid disorders developed in 19.5% of the participants (subclinical hyperthyroidism = 19, subclinical hypothyroidism = 3, overt hyperthyroidism = 1). Conclusion The current analysis provides an overview of the relationship between ICM volume and a higher risk of thyroid disorders and dysfunction.