gms | German Medical Science

68th Annual Meeting of the German Society of Neurosurgery (DGNC)
7th Joint Meeting with the British Neurosurgical Society (SBNS)

German Society of Neurosurgery (DGNC)

14 - 17 May 2017, Magdeburg

Intraoperative computed tomography versus iso-C 3D C-arm imaging for navigated spinal instrumentation

Meeting Abstract

  • Nils Hecht - Charité - Universitätsmedizin Berlin, Campus Charité Mitte, Neurochirurgische Klinik, Berlin, Deutschland
  • Hadya Yassin - Charité - Universitätsmedizin Berlin, Neurochirurgische Klinik, Campus Virchow Klinikum, Berlin, Deutschland
  • Marcus Czabanka - Charité - Universitätsmedizin Berlin, Campus Virchow-Klinikum, Neurochirurgische Klinik, Berlin, Deutschland
  • Bettina Föhre - Charité - Universitätsmedizin Berlin, Abteilung für Anästhesiologie m.S. operative Invensivmedizin, Campus Virchow Klinikum, Berlin, Deutschland
  • Thomas Liebig - Institut für Neuroradiologie, Institut für Neuroradiologie , Berlin, Deutschland
  • Peter Vajkoczy - Charité - Universitätsmedizin Berlin, Campus Mitte, Neurochirurgische Klinik, Berlin, Deutschland

Deutsche Gesellschaft für Neurochirurgie. Society of British Neurological Surgeons. 68. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie (DGNC), 7. Joint Meeting mit der Society of British Neurological Surgeons (SBNS). Magdeburg, 14.-17.05.2017. Düsseldorf: German Medical Science GMS Publishing House; 2017. DocDI.25.01

doi: 10.3205/17dgnc323, urn:nbn:de:0183-17dgnc3239

Published: June 9, 2017

© 2017 Hecht et al.
This is an Open Access article distributed under the terms of the Creative Commons Attribution 4.0 License. See license information at



Objective: Recent meta-analysis have evidenced the superior accuracy of navigated spinal instrumentation compared to non-navigated techniques. However, the benefit of intraoperative computed tomography (iCT) compared to iso-C 3D C-arm-based navigation remains unclear. The aim of the present study was to report our experience and accuracy of navigated pedicle screw insertion with iCT or 3D C-arm-based spinal imaging in 254 consecutive patients.

Methods: After exposure and attachment of the navigation tracking device, a first iCT or 3D C-arm scan was performed with automatic patient/image co-registration and navigated screw insertion. Screw positioning was then intraoperatively assessed by a second iCT or 3D C-arm scan, based upon which the intraoperative accuracy was determined. In cases that required intraoperative screw revision, navigated repositioning was performed based on the second iCT or 3D C-arm scan. Thereafter, a third iCT or 3D C-arm scan was performed to confirm repositioning. In cases with 3D C-arm navigation, a postoperative CT scan was routinely performed, based upon which the final accuracy was determined compared to the final iCT scan. The general intraoperative screw placement assessability through iCT or 3D C-arm and the intraoperative and final accuracies were retrospectively reviewed and analyzed by an independent observer.

Results: Between 2013 and 2016, 1527 pedicle screws were implanted in 260 patients with either iCT (1219 screws) or 3D C-arm (308 screws) based spinal navigation and automatic patient/image co-registration. The indications for surgery were degenerative disease (61%), infectious disease (11%), tumors (13%) and trauma (15%). Direct intraoperative screw assessment with iCT was successfully accomplished for each screw in all patients. In contrast, 39 of the screws implanted with the help of 3D C-arm imaging were intraoperatively not clearly assessable due to hardware artifacts and limited image quality. Regarding the overall precision rates, 3D C-arm-based spinal navigation yielded a comparable accuracy to iCT-based imaging (intraoperative accuracy: iCT 94.7% vs. 3D C-arm 89.4%; final accuracy: iCT 95.4% vs. 3D C-arm 91.6%). Regarding the region specific intraoperative performance, however, iCT-based screw insertion yielded a significantly higher accuracy in the cervical (iCT 98.8% vs. 3D C-arm 84.6%, *p<0.0001) and thoracic (iCT 96.4% vs. 3D C-arm 83.3%, *p<0.0001) regions, whereas no difference was detected in lumbar-sacral instrumentations (iCT 91.8% vs. 3D C-arm 90.0%; p>0.05).

Conclusion: Both iCT and 3D C-arm-based spinal navigation solutions are able to provide high pedicle screw accuracy rates. However, immediate intraoperative screw placement assessability and screw placement accuracy in the cervical/thoracic spine appear to be limited with intraoperative 3D C-arm imaging alone.