Impact of Iodinated Contrast Media in Patients Received Percutaneous Coronary Intervention: Focus on Thyroid Disease

Iodinated contrast media (ICM)-induced thyroid dysfunction: a review of potential mechanisms and clinical management

Iodinated contrast media (ICM) are extensively utilized in medical imaging to enhance tissue contrast, yet their impact on thyroid function has attracted increasing attention in recent years. ICM can induce thyroid dysfunction, with reported prevalence ranging from 1 to 15% and a higher incidence observed in individuals with pre-existing thyroid conditions or other risk factors like age, gender, underlying health issues, and repeated ICM exposure. This review summarized the classification of ICM and the potential mechanisms, risk assessment, and clinical management of ICM-induced thyroid dysfunction, especially in vulnerable populations such as pregnant women and elderly patients. Despite advancements that have enriched our understanding of the pathophysiology and treatment of ICM-induced thyroid dysfunction, critical knowledge gaps remain, such as the long-term effects of ICM on thyroid function, the dose-response relationship between ICM volume and thyroid dysfunction risk, and the ecological impacts of ICM. Therefore, further exploration of the underlying mechanisms of ICM-induced thyroid dysfunction and optimization of the management strategies will be crucial for the safe and effective use of ICM in clinical practice, and collaborative efforts between clinicians and researchers are essential to ensure that the risks of thyroid dysfunction do not outweigh the benefits of imaging.

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

OBJECTIVE

The use of iodinated contrast media (ICM) inevitably increases in conjunction with the growing number of epidural steroid injection (ESI) administrations. The purpose of this study was to investigate the relationship between thyroid functions and ICM exposure through ESI procedures.

DESIGN

This is a prospective observational study.

SETTING

The study was conducted at 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 ESI at our outpatient pain clinic comprised the study's population. Thyroid function tests (free triiodothyronine (FT3), free thyroxine (FT4), and thyroid-stimulating hormone (TSH)) were measured before and three weeks after the procedure.

RESULTS

A total of 124 participants (80 women and 44 men) were analyzed. 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 no patient developed thyroid disorders.

CONCLUSION

The current study presents an analysis of the relationship between ICM and thyroid functions in the ESI population.

Iodine-Induced Hypothyroidism After Chemoembolization With Ethiodized Oil: A Case of Failure to Escape From Wolff-Chaikoff Effect (WCE)

Wolff-Chaikoff effect (WCE) is an acute physiologic response of the thyroid gland to high levels of iodine. The WCE is usually temporary, and the thyroid gland adjusts to high iodine levels within days or weeks. It is a protective mechanism and a failure to escape from it can result in thyroid dysfunction. Hypothyroidism is rare but more likely in patients who have had thyroid disease, are under stress, or are exposed to high iodine concentrations for a long time. The use of iodinated contrast media in radiologic studies or invasive medical procedures is a common source of excessive iodine exposure and can lead to thyroid disfunction. Despite the frequent use of contrast media in health care, the thyroid dysfunction associated with their use is poorly recognized. We report a patient who developed iodine-induced hypothyroidism after chemoembolization of recurrent chylothorax with ethiodized oil (Lipiodol®, Villepinte, France). This case report raises awareness of the importance of the physiologic WCE as well as the relevance of monitoring thyroid function when using iodinated contrast media in patients with specific risk factors.