Investigation of radiation dose around C-arm fluoroscopy and relevant cancer risk to operating room staff.

This study aimed to evaluate the ambient dose equivalent around a C-arm device during spinal surgeries and determine the optimum locations for the surgeon and staff to keep radiation exposure as low as reasonably achievable. Furthermore, cancer risk incidence was estimated using the excess relative risk (ERR) concept of the biologic effects of ionizing radiation VII report for operating room (OR) staff. A lateral projection of the C-arm setup was considered in the current study. The ambient dose equivalent rate was measured using an electronic dosimeter in 30° steps all around for 1, and 1.6-m heights as well as 1, and 2-m distances away from a water tank (scattering medium). By assuming a typical workload, the annual ambient dose and a maximum number of permissible operations were determined. For a worst-case scenario, the dose was used to estimate the ERR for various organs including prostate, ovary, breast, lung, thyroid, and colon for attained ages of 35, 40, and 50 years. The maximum ambient dose equivalent rate was seen at 330° and 30° (about 600 µSv/h at 1 m height and a distance of 1 m from the scattering medium). The corresponding permissible workload for an OR staff was about 30,660 operations. Based on the obtained results, 60° next to the image intensifier was the optimum position for the surgeon, while 30° next to the tube was the worst position because of backscattered radiation. The ERR results showed that the lung and colon have the highest cancer risk incidence among the considered organs for both males and females, respectively.