Effective radiation dose reduction in computed tomography-guided spinal injections: a prospective, comparative study with technical considerations

Despite the good general patient acceptance, high patient comfort, safety and precision in the needle placement, exposure to radiation in computed tomography (CT)guided spinal interventions remains a serious concern, and is often used to argue against its use. The aim of this study was to determine the technical possibilities of reducing the radiation dose in CT-guided epidural and periradicular injections in lumbar spine. We evaluated the possibilities of reducing radiation dose to the patient and operator during CT-guided injections on the lumbar spine using the following steps: significant reduction of the tube current and energy used for the topogram-acquisition, narrowing the area of interest in spiral CTmode and reduction of tube current and radiation energy in the final intervention mode. Fifty-three CT-guided spinal injections were performed in the lumbar spine (34 epidural lumbar, 19 lumbar periradicular) using a low-dose protocol in non-obese patients and compared with 1870 CT-guided injections from the year 2010, when a standard dose protocol was used. Technical considerations on radiation dose reduction were provided. An average dose reduction of 85% was achieved using the low-dose protocol in CTguided epidural and periradicular injections in lumbar spine without showing any effect on safety or precision.