A new study published in Spine compares intraoperative CT to 3-D C-arm-based spinal navigation during procedures that require posterior pedicle screw implantation.
Study authors examined 260 patients who had 1,527 pedicle screws implanted over the three-year period between 2013 and 2016. Most patients—1,219—underwent intraoperative CT to place the screws while 308 patients had screws placed with 3-D C-arm spinal navigation. The screws were assessed intraoperatively with a second image to ensure accuracy and surgeons performed immediate revision when necessary.
Study authors found:
1. All patients who underwent the procedure with intraoperative CT were able to have immediate assessment of the implantable screws while 39 of the screws weren't clearly accessible with the 3-D C-arm imaging to examine accuracy.
2. Both imaging systems had comparable intraoperative accuracy; the intraoperative CT had 94.7 percent accuracy and the 3-D C-arm navigation had 89.4 percent accuracy.
3. Immediately correcting misplaced screws was possible with both imaging systems. Around 95 percent of the intraoperative CTs reported final accuracy, compared to 91.6 percent of 3D C-arm placed screws.
4. The intraoperative CT navigation had higher final accuracy rates in the cervical and thoracic spine; in both regions, the 3D C-arm had just under 89 percent accuracy while the intraoperative CT reported 99.5 percent accuracy in the cervical spine and 97.7 percent accuracy in the thoracic spine.
5. Study authors concluded, "Both iCT and 3D C-arm-based spinal navigation provides high pedicle screw accuracy rates. Immediate screw accessibility and placement accuracy in the cervical-thoracic spine, however, appear to be limited with intraoperative 3-D C-arm imaging alone."