METHODS: In total, 14 screws were placed. All screws were grade A on the Gertzbein-Robbins scale. The mean surface distance difference between rCT and sCT on a reconstructed software model was -0.02 ± 0.05 mm, the mean absolute surface distance was 0.24 ± 0.05 mm, and the mean absolute error of radiodensity was 92.88 ± 10.53 HU. The overall mean tip distance for the sCT versus rCT was 1.74 ± 1.1 versus 2.36 ± 1.6 mm (p = 0.24); mean tail distance for the sCT versus rCT was 1.93 ± 0.88 versus 2.81 ± 1.03 mm (p = 0.07); and mean angular deviation for the sCT versus rCT was 3.2° ± 2.05° versus 4.04°± 2.71° (p = 0.53).
CONCLUSIONS: MRI-based sCT yielded results comparable to those of rCT in both morphometric analysis and robot-assisted lumbosacral screw placement in a cadaver study.
方法:总共,放置了14个螺钉。所有螺钉均为Gertzbein-Robbins量表上的A级。在重建的软件模型上,rCT和sCT之间的平均表面距离差为-0.02±0.05mm,平均绝对表面距离为0.24±0.05mm,放射性密度的平均绝对误差为92.88±10.53HU。sCT与rCT的总平均尖端距离为1.74±1.1对2.36±1.6mm(p=0.24);sCT与rCT的平均尾部距离为1.93±0.88对2.81±1.03mm(p=0.07);sCT与rCT的平均角度偏差为3.2°±2.05°对4.04°±2.71°(p=0.53)。
结论:在尸体研究中,基于MRI的sCT在形态测量分析和机器人辅助的腰骶螺钉置入方面均产生了与rCT相当的结果。