Purpose: This study was conducted to characterise the O-arm® surgical imaging system in terms of patient organ doses and medical staff occupational exposure during three-dimensional thoracic spine and pelvic examinations.
Methods: An anthropomorphic phantom was used to evaluate absorbed organ doses during a three-dimensional thoracic spine scan and a three-dimensional pelvic scan with the O-arm®. Staff occupational exposure was evaluated by constructing an ambient dose cartography of the operating theatre during a three-dimensional pelvic scan as well as using an anthropomorphic phantom to simulate the O-arm® operator.
Results: Patient organ doses ranged from 30 ± 4 μGy to 20.0 ± 3.0 mGy and 4 ± 1 μGy to 6.7 ± 1.0 mGy for a three-dimensional thoracic spine and pelvic examination, respectively. For a single three-dimensional acquisition, the maximum ambient equivalent dose at 2 m from the iso-centre was 11 ± 1 μSv.
Conclusion: Doses delivered to the patient during a three-dimensional thoracic spine image acquisition were found to be significant with the O-arm®, but lower than those observed with a standard computed tomography examination. The detailed dose cartography allows for the optimisation of medical staff positioning within the operating theatre while imaging with the O-arm®.
Keywords: 3D surgical imaging system; Dosimetry; O-arm; Organ dose; Staff and patient radiation exposure.