Periradicular Infiltration of the Cervical Spine: How New CT Scanner Techniques and Protocol Modifications Contribute to the Achievement of Low-Dose Interventions.

Purpose CT-guided periradicular infiltration of the cervical spine is an effective symptomatic treatment in patients with radiculopathy-associated pain syndromes. This study evaluates the robustness and safety of a low-dose protocol on a CT scanner with iterative reconstruction software. Materials and Methods A total of 183 patients who underwent periradicular infiltration therapy of the cervical spine were included in this study. 82 interventions were performed on a new CT scanner with a new intervention protocol using an iterative reconstruction algorithm. Spot scanning was implemented for planning and a basic low-dose setup of 80 kVp and 5 mAs was established during intermittent fluoroscopy. The comparison group included 101 prior interventions on a scanner without iterative reconstruction. The dose-length product (DLP), number of acquisitions, pain reduction on a numeric analog scale, and protocol changes to achieve a safe intervention were recorded. Results The median DLP for the whole intervention was 24.3 mGy* cm in the comparison group and 1.8 mGy* cm in the study group. The median pain reduction was - 3 in the study group and - 2 in the comparison group. A 5 mAs increase in the tube current-time product was required in 5 patients of the study group. Conclusion Implementation of a new scanner and intervention protocol resulted in a 92.6 % dose reduction without a compromise in safety and pain relief. The dose needed here is more than 75 % lower than doses used for similar interventions in published studies. An increase of the tube current-time product was needed in only 6 % of interventions.