Original Article

The Korean Journal of Pain 2020; 33(1): 73-80

Published online January 1, 2020 https://doi.org/10.3344/kjp.2020.33.1.73

Copyright © The Korean Pain Society.

Radiation exposure to the eyes and thyroid during C-arm fluoroscopy-guided cervical epidural injections is far below the safety limit

Eun Joo Choi1 , Gwangcheol Go1 , Woong Ki Han1 , and Pyung-Bok Lee1,2

1Department of Anesthesiology and Pain Medicine, Seoul National University Bundang Hospital, Seongnam, Korea
2Department of Anesthesiology and Pain Medicine, Seoul National University College of Medicine, Seoul, Korea

Correspondence to:Pyung-Bok Lee
Department of Anesthesiology and Pain Medicine, Seoul National University Bundang Hospital, 82 Gumi-ro 173beongil, Bundang-gu, Seongnam 13620, Korea
Tel: +82-31-787-7499
Fax: +82-31-787-4063
E-mail: painfree@snubh.org

Received: October 21, 2019; Revised: October 23, 2019; Accepted: October 23, 2019

This is an open-access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0/), which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.



The aim of this study was to evaluate radiation exposure to the eye and thyroid in pain physicians during the fluoroscopy-guided cervical epidural block (CEB).


Two pain physicians (a fellow and a professor) who regularly performed C-arm fluoroscopy-guided CEBs were included. Seven dosimeters were used to measure radiation exposure, five of which were placed on the physician (forehead, inside and outside of the thyroid protector, and inside and outside of the lead apron) and two were used as controls. Patient age, sex, height, and weight were noted, as were radiation exposure time, absorbed radiation dose, and distance from the X-ray field center to the physician.


One hundred CEB procedures using C-arm fluoroscopy were performed on comparable patients. Only the distance from the X-ray field center to the physician was significantly different between the two physicians (fellow: 37.5 ± 2.1 cm, professor: 41.2 ± 3.6 cm, P = 0.03). The use of lead-based protection effectively decreased the absorbed radiation dose by up to 35%.


Although there was no difference in radiation exposure between the professor and the fellow, there was a difference in the distance from the X-ray field during the CEBs. Further, radiation exposure can be minimized if proper protection (thyroid protector, leaded apron, and eyewear) is used, even if the distance between the X-ray beam and the pain physician is small. Damage from frequent, low-dose radiation exposure is not yet fully understood. Therefore, safety measures, including lead-based protection, should always be enforced.

Keywords: Anesthesia, Epidural, Cervical Vertebrae, Chronic Pain, Eye, Fluoroscopy, Physicians, Protection, Radiation, Thyroid Gland