Quantifying O-arm Radiation Exposure to Operating Room Personnel during Simulated Spinal Fusion for Adolescent Idiopathic Scoliosis Using Real-Time Dosimetry

ABSTRACT: Background Intraoperative O-arm imaging for pedicle screw navigation or robotics is commonly utilized in the operative management of adolescent idiopathic scoliosis (AIS). Previous studies have evaluated the intraoperative patient dose secondary to O-arm image acquisition, but radiation exposure to surgical team members in pediatric spine surgery has not been described. Our study aims to quantify the amount of radiation experienced by OR personnel during a simulated posterior spinal fusion for AIS. Methods A phantom was utilized to simulate the torso of an adolescent patient. Four total O-arm 3D imaging scans were performed on both low-dose and standard-dose settings with and without lead shielding. RaySafe i3 real-time dosimeters were placed in simulated positions of the OR team and measured radiation dose in μSv (Figure 1). Paired t-tests, non-linear regression, and Pearson correlation analyses were used to compare radiation dose, distance, and lead protection effects. Results The attending surgeon was closest to the O-arm at 120 cm and experienced 33 μSv at standard dose and 15.8 μSv at low dose when not wearing lead. The resident physician (204 cm) experienced the second highest radiation exposure at 5.8 μSv at standard dose followed by the circulating nurse (324 cm, 5.3 μSv), anesthesiologist (255 cm, 3.1 μSv), and neuromonitoring technician (400 cm, 2.8 μSv). The remainder of the dosimeter positions including the surgical core had less than 2 μSv exposure. The low dose O-arm scan resulted in lower exposures to all staff members (p < 0.05). With lead shielding (both lead aprons and mobile barriers), all staff dosimeters recorded less than 2 μSv of radiation exposure at all positions (p < 0.05). Conclusions Standing in the surgical core during O-arm image acquisition does not result in reduction in radiation exposure compared to standing behind a lead shield or wearing lead in the operating room. Low-dose O-arm imaging settings lowered radiation exposure for all operating room personnel. The use of lead shielding reduced exposure at every position. The inverse square law of radiation exposure was observed in this study. Significance Radiation exposure to the OR team is minimal when utilizing lead protection, allowing all personnel to safely remain in the OR during pediatric spine surgery image acquisition. Key Concepts • In a simulated pediatric spine surgery environment, intra-operative O-arm imaging produced measurable but low occupational radiation exposure that decreased with increasing distance from the source. • Use of low-dose O-arm protocols significantly reduced scatter radiation exposure to all operating room personnel compared with standard-dose imaging. • Lead shielding, including mobile barriers and personal lead protection, effectively reduced occupational radiation exposure to near-zero levels across all simulated personnel positions. • Radiation exposure demonstrated a strong inverse relationship with distance from the O-arm, with the highest doses occurring closest to the imaging source. • Occupational exposure levels observed in this study were well below established safety thresholds, supporting that OR personnel do not need to leave the operating room during O-arm image acquisition.